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Zvichangobva kuratidzwa kuti kushandiswa kweiyo ultrasound kunowedzera goho retishu mune ultrasound-inobatsirwa yakanaka tsono aspiration (USeFNAB) zvichienzaniswa neyakajairwa yakanaka tsono aspiration (FNAB).Parizvino, hukama pakati pebevel geometry uye tip kufamba hauna kunyatso dzidza.Muchidzidzo ichi, takaongorora zvimiro zvetsono resonance uye deflection amplitude yeakasiyana tsono bevel geometries ane akasiyana bevel kureba.Uchishandisa yakajairika 3.9 mm beveled lancet, iyo tip deflection power factor (DPR) mumhepo nemvura yaive 220 uye 105 µm/W, zvichiteerana.Iyi yakakwirira kudarika axisymmetric 4mm beveled tip, inopa 180 uye 80 µm/W DPR mumhepo nemvura, zvichiteerana.Ichi chidzidzo chinosimbisa kukosha kwehukama pakati pekukotama kuomarara kwebevel geometry mumamiriro ezvakasiyana nzira yekuisa, uye saka inogona kupa nzwisiso yenzira dzekudzora mushure mekubaya kucheka chiito nekushandura tsono bevel geometry, iyo yakakosha.yeUSeFNAB application yakakosha.
Fine-needle aspiration biopsy (FNA) inzira yekuwana masamples ematishu enofungidzirwa kuti pathology1,2,3 uchishandisa tsono.Iyo Franseen tip yakaratidzwa kupa yepamusoro yekuongorora maitiro pane yakajairwa lancet4 uye Menghini5 matipi.Axisymmetric (kureva circumferential) materu anokurudzirwawo kuti awedzere mukana wezvimiro zvakaringana zve histopathologically.
Panguva yebiopsy, tsono inopfuudzwa nepakati peganda nematishu kuti iwane maronda anofungidzirwa.Zvidzidzo zvenguva pfupi zvakaratidza kuti ultrasound inogona kuderedza simba rekupinda rinodiwa kuti uwane zvinyoro zvinyoro7,8,9,10.Needle bevel geometry yakaratidzwa kuti inokanganisa masimba ekubatanidza tsono, semuenzaniso, mabheji akareba akaratidzwa kuva nemasimba ekupinza kwematishu11.Mushure mekunge tsono yapinda pamusoro pematishu, kureva mushure mekuputika, simba rekucheka retsono rinogona kuva 75% yekubatana kwesimba retsono ne tissue12.Zvave zvichiratidzwa kuti muchikamu chekupedzisira-puncture, ultrasound (ultrasound) inowedzera kushanda kwekuongorora zvinyoro zvinyoro biopsy.Mamwe maitiro e-ultrasound-enhanced bone biopsy akagadzirwa kuti atore masampula enyama yakaoma, asi hapana mhedzisiro yakataurwa inovandudza goho rebiopsy.Zvidzidzo zvakawanda zvakasimbisawo kuti mechanical displacement inowedzera kana ichiiswa kune ultrasonic stress16,17,18.Nepo kune zvakawanda zvidzidzo zveaxial (longitudinal) static masimba mukudyidzana kwetsono-tishu19,20, pane zvishoma zvidzidzo pamusoro peiyo temporal dynamics uye geometry yetsono bevel pasi pe ultrasonic FNAB (USeFNAB).
Chinangwa chechidzidzo ichi chaive chekuferefeta mabatiro eakasiyana bevel geometries pakufamba kwetsono muromo mutsono inofambiswa ne ultrasonic bending.Kunyanya, isu takaongorora mabatiro ejekiseni repakati pane tsono yepipi kutsauka mushure mekubaya kwechinyakare mabhero etsono (kureva, USeFNAB tsono dzezvinangwa zvakasiyana sekusarudza kushuvira kana kutora matishu akapfava.
Akasiyana-siyana mabevel geometri akaiswa muchidzidzo ichi.(a) Tsanangudzo yeLancet inoenderana neISO 7864:201636 apo \(\ alpha\) ndiro bhero rekutanga, \(\theta\) ndiyo kona yekutenderera yebevel rechipiri, uye \(\phi\) ndiro rechipiri bevel. angle., pakutenderera, mumadhigirii (\(^\circ\)).(b) Linear asymmetrical single step chamfers (inonzi "standard" muDIN 13097:201937) uye (c) Linear axisymmetric (circumferential) single step chamfers.
Maitiro edu anotanga nekuenzanisira shanduko mukupeta wavelength pamwe nebevel reyakajairwa lancet, axisymmetric, uye asymmetric single-stage bevel geometries.Isu takazoverengera parametric kudzidza kuti tiongorore mhedzisiro yepombi inotsvedza uye kureba pane mechaniki fluidity yekutamisa.Izvi zvinodikanwa kuti uone hurefu hwakakwana hwekugadzira prototype tsono.Zvichienderana nekuenzanisa, tsono prototypes dzakagadzirwa uye hunhu hwavo hwekudzokororwa hwakaratidzwa nekuyeresa voltage reflection coefficients uye kuverenga simba rekufambisa simba mumhepo, mvura uye 10% (w/v) ballistic gelatin, kubva kwakadzikwa frequency yekushandisa. .Pakupedzisira, kufungidzira kwepamusoro-soro kunoshandiswa kuyera zvakananga kutsauka kwevheji yekukotama pamucheto wetsono mumhepo nemvura, pamwe nekufungidzira simba remagetsi rinounzwa pane imwe neimwe oblique angle uye geometry yereshiyo yemagetsi emagetsi. DPR) kune iyo jekiseni yepakati..
Sezvinoratidzwa mumufananidzo 2a, shandisa 21 gauge chubhu (0.80 mm OD, 0.49 mm ID, chubhu yemadziro ukobvu 0.155 mm, madziro akajairika) kutsanangura chubhu yetsono ine chubhu kureba (TL) uye bevel angle (BL) zvinoenderana neISO. 9626:201621) mu 316 simbi isina tsvina (Young's modulus 205 \(\text {GN/m}^{2}\), density 8070 kg/m\(^{3}\) uye Poisson's ratio 0.275).
Kutsunga kwekukotama wavelength uye kugadzirisa kweiyo inogumira element modhi (FEM) yetsono uye muganho mamiriro.(a) Kutemerwa kwebevel kureba (BL) uye pombi kureba (TL).(b) Matatu-dimensional (3D) finite element model (FEM) achishandisa harmonic point force \(\tilde{F}_y\vec {j}\) kutyaira tsono pedyo, kutsausa poindi, uye kuyera velocity pa zano (\ ( \tilde {u}_y\vec {j}\), \(\tilde{v}_y\vec {j}\)) kuverenga kuendeswa kwe mechanical fluidity.\(\lambda _y\) inotsanangurwa seredhiyo yekukotama inoenderana nesimba rakamira \(\tilde{F}_y\vec {j}\).(c) Tsanangudzo dzepakati pesimba rinokwevera zvinhu pasi, nzvimbo yemuchinjikwa-chikamu A, uye nguva dze inertia \(I_{xx}\) uye \(I_{yy}\) kumativi x uye y axes, zvichiteerana.
Sezvinoratidzwa mufig.2b,c, kune isingaperi (isingagumi) danda rine mhiri-sectional nzvimbo A uye pawavelength yakakura kudarika danda rakachinjika saizi, yakakombama (kana yakakombama) nhanho yenhanho \( c_{EI }\) inotarwa ne22 :
apo E is Young's modulus (\(\text {N/m}^{2}\)), \(\omega _0 = 2\pi f_0\) ndiyo inosimudzira angular frequency (rad/s), apo \( f_0 \ ) ndiyo mutsara wemutsetse (1/s kana Hz), ini inguva ye inertia yenzvimbo yakatenderedza axis yekufarira\((\text {m}^{4})\), \(m'=\ rho _0 A\ ) ndiwo huremu pahurefu hweyuniti (kg/m), apo \(\rho _0\) pane density\((\text {kg/m}^{3})\) uye A ndiye muchinjikwa chikamu chenzvimbo yedanda (xy plane) (\(\ zvinyorwa {m}^{2}\)).Sezvo simba rinoshandiswa mumuenzaniso wedu richifambirana ne vertical y-axis, kureva \(\ tilde{F}_y\vec {j}\), isu tiri kungofarira nguva yedunhu ye inertia yakatenderedza yakachinjika x-axis, kureva \(I_{xx}\), saka:
Kune inogumira element modhi (FEM), yakachena harmonic displacement (m) inofungidzirwa, saka kukwidziridza (\(\text {m/s}^{2}\)) inoratidzwa se \(\ partial ^2 \vec {u}/ \ chikamu t^2 = -\omega ^2\vec {u}\) se \(\vec {u}(x, y, z, t): = u_x\vec {i} + u_y\ vec {j } + u_z\vec {k}\) inzvimbo ine mativi matatu-dimensional displacement vector yakapihwa munzvimbo dzakarongwa.Panzvimbo peiyo yekupedzisira, zvinoenderana nekuita kwayo muCOMSOL Multiphysics software package (vhezheni 5.4-5.5, COMSOL Inc., Massachusetts, USA), iyo yekupedzisira deformation Lagrangian fomu yeiyo nhanho chiyero mutemo inopiwa sezvinotevera:
uko \(\vec {\nabla}:= \frac{\ partial}}{\partial x}\vec {i} + \frac{\ partial}}{\ partial y}\vec {j} + \frac{ \ partial }{\ partial z}\vec {k}\) ndiye tensor divergence opareta, \({\ underline{\sigma}}\) ndiye wechipiri Piola-Kirchhoff stress tensor (yechipiri kurongeka, \(\ zvinyorwa { N/ m}^{2}\)) uye \(\vec {F_V}:= F_{V_x}\vec {i}+ F_{V_y}\vec {j}+ F_{V_z}\vec {k} \) ndiyo body force vector (\(\text {N/m}^{3}\)) yevhoriyamu yega yega yakaremara, uye \(e^{j\phi }\) ndiyo phase angle vector\(\ phi \ ) ( kufara).Kwatiri, vhoriyamu simba remuviri i zero, modhi yedu inotora mutsara wejometri uye diki diki rakasimba deformation, kureva, uko \({\ underline{\varepsilon}}^{el}\) uye \({\ underline {\ varepsilon}}\) ndeye elastic strain uye yakazara dhizaini (yechipiri kurongeka, dimensionless), zvichiteerana.Hooke's constitutive isotropic elasticity tensor \(\underline{\underline{C}}\) inoverengerwa pachishandiswa Young's modulus E (\(\text {N/m}^{2}\)) uye ratio yaPoisson v inotarwa, saka kureva. \(\ underline{\ underline{C}}:=\ underline{\ underline{C}}(E,v)\) (mutsetse wechina).Saka kuverenga kwekushushikana kunova \({\ underline{\sigma}} := \ underline{\ underline{C}}:{\ underline{\varepsilon}}\).
Kuverenga kunoshandisa gumi-node tetrahedral element ine element saizi \(\le\) ye8 µm.Iyo tsono inofananidzwa muvacuum, uye kukosha kwekuchinjisa mechanical mobility (ms-1 N-1) inotsanangurwa se \(|\tilde{Y}_{v_yF_y}|= |\tilde{v}_y\vec { j}|/ |\ tilde{F}_y\vec {j}|\)24, apo \(\tilde{v}_y\vec {j}\) ndiko kubuda kwakaoma velocity yehandpiece uye \(\ tilde {F}_y\ vec {j }\) isimba rinotyaira rakaomarara riri kumucheto kwechubhu, sezvinoratidzwa mumufananidzo 2b.Shandura the mechanical fluidity in decibels (dB) uchishandisa ukoshi hwepamusoro sereferensi, kureva \(20\log _{10} (|\tilde{Y}|/ |\tilde{Y}_{max}|) \ ) .Zvose zvidzidzo zveFEM zvakaitwa pahuwandu hwe29.75 kHz.
Magadzirirwo etsono (Fig. 3) inosanganisira yakajairika 21-gauge hypodermic tsono (Cat. Nha. simbi , B. Braun Melsungen AG, Melsungen, Germany) akashongedzerwa nepurasitiki Luer Lock sleeve yakagadzirwa nepolypropylene kumagumo uye yakagadziridzwa zvakakodzera kumagumo.Iyo tsono chubhu inotengeswa kune waveguide sezvakaratidzwa mumufananidzo 3b.Mawaveguides akadhindwa paStainless steel 3D printer (EOS 316L Stainless steel paEOS M 290 3D printer, 3D Formtech Oy, Jyväskylä, Finland) ndokubva anamatira kuLangevin sensor achishandisa M4 mabhaudhi.Iyo Langevin sensor ine 8 piezoelectric mhete zvinhu zvakatakurwa kumagumo ese nemasasi maviri.
Iwo mana mhando dzematipi (mufananidzo), inotengeswa lancet (L) uye matatu akagadzirwa axisymmetric single-stage bevels (AX1-3) airatidzwa nebevel kureba (BL) ye4, 1.2 uye 0.5 mm, zvichiteerana.(a) Kuvhara-kupedzwa kwetsono muromo.(b) Maonero epamusoro emapini mana akatengeswa kune 3D yakadhindwa waveguide ndokuzobatana neLangevin sensor ine M4 mabhaudhi.
Matatu axisymmetric bevel matipi (Fig. 3) akagadzirwa (TAs Machine Tools Oy) ane bevel kureba (BL, sezvinotsanangurwa Fig. 2a) ye4.0, 1.2 uye 0.5 mm, inoenderana \(\ approx) 2 \(^ \ circ\), 7\(^\circ\) uye 18\(^\circ\) zvichiteerana.Huremu hwewaveguide netsono ndeye 3.4 ± 0.017 g (zvinoreva ± sd, n = 4) yebevel L uye AX1-3, zvakateerana (Quintix\(^\circledR\) 224 Dhizaini 2, Sartorius AG, Göttingen, Germany) .Kune L neAX1-3 bevels muFigure 3b, kureba kwese kubva kumuromo wetsono kusvika kumagumo epurasitiki sleeve yaive 13.7, 13.3, 13.3, uye 13.3 cm, zvichiteerana.
Pamagadzirirwo ese etsono, kureba kubva kumuromo wetsono kusvika kumuromo wewaveguide (kureva, kune weld area) yaive 4.3 cm, uye chubhu yetsono yakatarisa neyakachekwa kumusoro (kureva, parallel kune Y axis) , sezvinoratidzwa mumufananidzo.c (Mufananidzo 2).
Chinyorwa chetsika muMATLAB (R2019a, The MathWorks Inc., Massachusetts, USA) chinoshanda pakombuta (Latitude 7490, Dell Inc., Texas, USA) chakashandiswa kugadzira mutsara we sinusoidal sweep kubva pa25 kusvika 35 kHz kwemasekonzi manomwe, kupfuura A digital-to-analog (DA) converter (Analog Discovery 2, Digilent Inc., Washington, USA) inoshandura kuchiratidzo cheanalogi.Chiratidzo cheanalog \(V_0\) (0.5 Vp-p) chakabva chawedzerwa neredhiyo yakatsaurirwa frequency (RF) amplifier (Mariachi Oy, Turku, Finland).Inodonha amplified voltage \({V_I}\) kubva kuRF amplifier ine inobuda impedance ye50 ohms inopihwa kune transformer yakavakirwa mukati metsono chimiro ine impedance yekupinza ye50 ohms.Langevin transducers (kumberi nekumashure kunorema-duty multilayer piezoelectric transducers) anoshandiswa kugadzira masaisai emuchina.Iyo tsika RF amplifier ine mbiri-channel yakamira wave simba factor (SWR) mita inorekodha chiitiko \({V_I}\) uye inoratidzira amplified voltage\(V_R\) muanalog-to-digital (AD) modhi.ine sampling rate ye300 kHz Converter (analogue Discovery 2).Chiratidzo chekusimudzira ndeye amplitude yakagadziridzwa pakutanga uye kumagumo kudzivirira kuwandisa iyo amplifier yekupinda neinotenderera.
Kushandisa chinyorwa chetsika chakaitwa muMATLAB, iyo frequency response function (FRF), kureva \(\tilde{H}(f)\), yakafungidzirwa pasina Indaneti pachishandiswa nzira mbiri dzekuyera sinusoidal sweep (Fig. 4), iyo inotora mutsara munguva.invariant system.Pamusoro pezvo, 20 kusvika 40 kHz bhendi pass sefa inoshandiswa kubvisa chero ma frequency asingadiwe kubva pachiratidzo.Tichireva dzidziso yemitsara yekutapurirana, muchiitiko ichi \(\tilde{H}(f)\) yakaenzana nevoltage reflection coefficient, kureva \(\rho _{V} \equiv {V_R}/{V_I}\ ) \) inodzikira kusvika \({V_R}^ 2 /{V_I}^2\ ) yakaenzana \(|\rho _{V}|^2\).Muzviitiko apo mhedziso yesimba remagetsi emagetsi inodiwa, chiitiko simba \ (P_I\) uye inoratidzwa simba \ (P_R\) simba (W) inoverengerwa nekutora rms kukosha (rms) yevoltage inoenderana, semuenzaniso.kune tambo yekufambisa ine sinusoidal excitation \( P = {V}^2/(2Z_0)\)26, apo \(Z_0\) yakaenzana ne50 \(\Omega\).Simba remagetsi rinopihwa mutoro \(P_T\) (kureva, iyo yakaiswa mukati) inogona kuverengerwa se \(|P_I - P_R |\) (W RMS), pamwe chete nekufambisa kwesimba kwesimba (PTE) uye muzana ( %) inogona kutariswa kuti chimiro chinopihwa sei, saka 27:
The acicular modal frequencies \(f_{1-3}\) (kHz) nemafekitari anoenderana ekutamisa simba \(\text {PTE}_{1{1{-}3} \) zvino zvinofungidzirwa kushandisa FRF.FWHM (\(\text {FWHM}_{1{-}3}\), Hz) inofungidzirwa zvakananga kubva \(\text {PTE}_{1{-}3}\), kubva paTable 1 A divi rimwe linear spectrum inowanikwa pane yakatsanangurwa modal frequency \(f_{1-3}\).
Kuyerwa kweiyo frequency mhinduro (AFC) yezvimiro zvetsono.A sinusoidal two-channel sweep measurement25,38 inoshandiswa kuwana frequency remhinduro basa \(\tilde{H}(f)\) uye mhinduro yayo yekufungidzira H(t).\({\ mathcal {F}}\) uye \({\ mathcal {F}}^{-1}\) inomiririra shanduko yeFourier yedhijitari nekupesana kwayo, zvichiteerana.\(\tilde{G}(f)\) zvinoreva chigadzirwa chezviratidzo zviviri mu frequency domain, semuenzaniso \(\tilde{G}_{XrX}\) zvinoreva inverse scan product\(\tilde{ X} r (f)\ ) uye donhedza voltage \(\tilde{X}(f)\) zvichiteerana.
Sezvinoratidzwa muMufananidzo 5, kamera yepamusoro-soro (Phantom V1612, Vision Research Inc., NJ, USA) ine macro lens (MP-E 65mm, \ (f \) / 2.8, 1-5 \).(\ nguva\), Canon Inc., Tokyo, Japan), kurekodha deflections panguva yekukotama excitation (single-frequency, continuous sinusoid) pamafrequency e27.5-30 kHz.Kugadzira mepu yemumvuri, chinhu chakatonhodzwa cheyakanyanya kusimba chena LED (chikamu nhamba: 4052899910881, chena LED, 3000 K, 4150 lm, Osram Opto Semiconductors GmbH, Regensburg, Germany) yakaiswa kuseri kwemuromo wetsono.
Kutarisa kumberi kwechiedzo setup.Kudzika kunopimwa kubva pamusoro pepakati.Chimiro chetsono chinosungirirwa uye chakaiswa patafura yekufambisa mota.Shandisa kamera yekumhanya ine lenzi yekukudza yakakwira (5\(\x\)) kuyera kutsauka kwekona.Zviyero zvese zviri mumamilimita.
Pamhando yega yega yetsono bevel, takarekodha mazana matatu mafuremu e-high-speed kamera inoyera 128 \(\x\) 128 pixels, imwe neimwe ine spatial resolution ye1/180 mm (\(\ approx) 5 µm), ine kugadziriswa kwechinguva kwe310,000 mafuremu pasekondi.Sezvinoratidzwa mumufananidzo 6, furemu yega yega (1) inochekwa (2) zvekuti muromo wetsono uri mumutsetse wekupedzisira (pazasi) wefuremu, uye histogram yemufananidzo (3) inoverengerwa, saka Canny. Zvikumbaridzo zve1 uye 2 zvinogona kutsanangurwa.Wobva waisa Canny edge discovery 28(4) neSobel opareta 3 \(\nguva\) 3 woverengera zvinzvimbo zveasiri-hypotenuse pixels (akanyorwa \(\mathbf {\nguva }\)) pasina cavitation 300 nguva nhanho.Kuti uone huwandu hwekutsauswa kwetipi, verenga kubva (uchishandisa musiyano wepakati algorithm) (6) uye sarudza furemu (7) ine kunyanyisa kwenzvimbo (kureva peak) yekutsauka.Mushure mekutarisa kwekuona kwecavitation-isina mupendero, maviri mafuremu (kana maviri mafuremu ane nguva yehafu yenguva) akasarudzwa (7) uye kutsauka kwechipimo kwakayerwa (kwainzi \(\ mathbf {\ nguva } \)).Izvo zviri pamusoro zvinoiswa muPython (v3.8, Python Software Foundation, python.org) uchishandisa OpenCV Canny edge yekuona algorithm (v4.5.1, open source library vision library, opencv.org).Pakupedzisira, deflection power factor (DPR, µm/W) inoverengwa sereshiyo yepeak-to-peak deflection kune inofambiswa magetsi simba \(P_T\) (Wrms).
Uchishandisa 7-nhanho algorithm (1-7), kusanganisira kurima (1-2), Canny edge yekuona (3-4), kuverenga, kuyera nzvimbo yepixel yetipi inotsvedza kumucheto uchishandisa dzakatevedzana mafuremu akatorwa kubva kumusoro- yekumhanyisa kamera pa310 kHz ( 5) uye nguva yaro kubva (6), uye, pakupedzisira, huwandu hwekutsauka kwetipi hunoyerwa pamafuremu anotariswa anotariswa (7).
Kuyerwa mumhepo (22.4-22.9 ° C), mvura yakasvibiswa (20.8-21.5 ° C) uye 10% (w/v) aqueous ballistic gelatin (19.7-23.0 ° C , \(\ zvinyorwa {Honeywell} ^{\ zvinyorwa { TM}}\) \(\text {Fluka}^{\text {TM}}\) Bovine nePork Bone Gelatin yeType I Ballistic Analysis, Honeywell International, North Carolina, USA).Kupisa kwakayerwa neK-type thermocouple amplifier (AD595, Analog Devices Inc., MA, USA) uye K-type thermocouple (Fluke 80PK-1 Bead Probe No. 3648 type-K, Fluke Corporation, Washington, USA).Shandisa yakamira yakamira mota Z-axis nhanho (8MT50-100BS1-XYZ, Standa Ltd., Vilnius, Lithuania) kuyera hudzamu kubva kune media media (yakaiswa sekwakabva Z-axis) nechisarudzo che5 µm padanho.
Sezvo saizi yemuenzaniso yaive diki (n = 5) uye zvakajairika zvaisakwanisa kufungidzirwa, maviri-sample maviri-akaviri Wilcoxon rank sum test (R, v4.0.3, R Foundation for Statistical Computing, r-project.org) yakashandiswa. kuenzanisa huwandu hwekusiyana kwetsono tipi yemabhero akasiyana.Mienzaniso mitatu yakaitwa pamateru ega ega, saka kururamisa kweBonferroni kwakashandiswa neyakagadziriswa kukosha kwe0.017 uye kukanganisa kwe5%.
Reference inoitwa kuFig. 7 pazasi.Pa29.75 kHz, iyo yakakombama hafu yewavelength (\(\lambda _y/2\)) ye21-gauge tsono iri \(\inenge) 8 mm.Kukombama kwewavelength kunodzikira pamwe nemateru sezvainoswedera kumuromo.Pamuromo \(\ lambda _y/2\) pane akatsikwa mabevel e3, 1 uye 7 mm, zvichiteerana, kune akajairwa lancets (a), asymmetric (b) uye axisymmetric (c).Nokudaro, izvi zvinoreva kuti lancet ichasiyana ne \ (\ inenge \) 5 mm (nekuda kwekuti ndege mbiri dze lancet dzinoita nzvimbo ye 29.30), iyo asymmetrical slope ichasiyana ne 7 mm, uye symmetrical slope. ne1 mm.Axisymmetric slopes (pakati pesimba regiravhiti rinoramba rakafanana, saka chete ukobvu hwemadziro hunochinja pamateru).
Kushandiswa kwechidzidzo cheFEM pa29.75 kHz uye equation.(1) Verenga kupeta kwehafu-savha shanduko (\(\lambda _y/2\)) yerenzi (a), asymmetric (b) uye axisymmetric (c) oblique geometry (semumufananidzo 1a,b,c).)Avhareji \(\lambda_y/2\) ye lancet, asymmetric, uye axisymmetric slopes ndeye 5.65, 5.17, uye 7.52 mm, zvichiteerana.Ziva kuti ukobvu hwetipi hweasymmetric uye axisymmetric bevel inogumira ku \(\ approx) 50 µm.
Peak mobility \(|\tilde{Y}_{v_yF_y}|\) isanganiswa ye optimal chubhu kureba (TL) uye inclination urefu (BL) (Fig. 8, 9).Kune yakajairika lancet, sezvo saizi yayo yakagadziriswa, iyo yakakwana TL ndeye \ (\ approx \) 29.1 mm (Fig. 8).Kune asymmetric uye axisymmetric slopes (Fig. 9a, b, zvichiteerana), chidzidzo cheFEM chaisanganisira BL kubva ku1 kusvika ku7 mm, saka iyo yakakwana yeTL mitsara yaive kubva ku26.9 kusvika 28.7 mm (renji 1.8 mm) uye kubva 27.9 kusvika 29.2 mm (range 1.3 mm).)), zvichiteerana.Kune asymmetric materu (Fig. 9a), iyo optimal TL yakawedzera mutsara, ichisvika pabani paBL 4 mm, uyezve yakaderera kubva kuBL 5 kusvika ku7 mm.Kune axisymmetric slopes (Fig. 9b), iyo yakakwana TL inowedzera mutsara neBL elongation uye pakupedzisira inodzikama paBL kubva 6 kusvika 7 mm.Chidzidzo chakawedzerwa che axisymmetric slopes (Fig. 9c) yakaratidza imwe yakasiyana-siyana ye optimal TLs iri pa \ (\ approximate) 35.1-37.1 mm.Kune ese maBL, chinhambwe chiri pakati pemaseti maviri ezvakanyanya TLs \(\ approx\) 8 mm (yakaenzana \(\lambda _y/2\)).
Lancet kutapurirana kufamba pa29.75 kHz.Iyo tsono chubhu yakachinjika pane frequency ye 29.75 kHz, iyo vibration yakayerwa pamagumo uye yakaratidzirwa sehuwandu hwekufambiswa kwema mechanical mobility (dB inofananidzwa nehuwandu hunokosha) yeTL 26.5-29.5 mm (0.1 mm danho).
Zvidzidzo zveParametric zveFEM pane imwe nguva ye 29.75 kHz zvinoratidza kuti kufambisa kwekufambisa kweiyo axisymmetric tip haina kukanganiswa nekuchinja kwehurefu hwechubhu pane imwe yayo asymmetric.Kureba kweBevel (BL) uye kureba kwepombi (TL) zvidzidzo zveasymmetric (a) uye axisymmetric (b, c) bevel geometries mune frequency domain zvidzidzo uchishandisa FEM (muganho mamiriro anoratidzwa mumufananidzo 2).(a, b) TL yakabva pa26.5 kusvika pa29.5 mm (0.1 mm nhanho) uye BL 1-7 mm (0.5 mm nhanho).(c) Yakawedzerwa axisymmetric oblique angle kudzidza inosanganisira TL 25-40mm (0.05mm nhanho) uye 0.1-7mm (0.1mm nhanho) inoburitsa reshiyo inodiwa \(\lambda_y/2\) Mamiriro emuganhu akasununguka anofamba etipi anogutsikana.
Chimiro chetsono chine mafambiro matatu echisikigo \(f_{1-3}\) akakamurwa kuita nzvimbo dzakaderera, dzepakati nepamusoro sezviri kuratidzwa muTebhurari 1. Saizi yePTE inoratidzwa muMufananidzo 10 uye yoongororwa muFigure 11. Pazasi pane iwo mhedzisiro yenzvimbo yega yega modal:
Typical rekodha instantaneous simba kutamisa kushanda zvakanaka (PTE) amplitudes akawanikwa achishandisa sinusoidal excitation pamwe swept frequency pakadzika 20 mm nokuda lancet (L) uye axisymmetric materu AX1-3 mumhepo, mvura uye gelatin.A one-side spectrum anoratidzwa.Iyo yakayerwa frequency mhinduro (300 kHz sampuli mwero) yaive yakaderera-pasi yakasefa uye ndokuzoderedzwa nechikamu che200 chekuongorora modal.Chiratidzo-ku-ruzha reshiyo \(\le\) 45 dB.Iyo PTE chikamu (yepepuru ine doti mutsara) inoratidzwa mumadhigirii (\(^{\circ}\)).
Ongororo yemhinduro yemodal inoratidzwa muMufananidzo 10 (zvinoreva ± chiyero chakatsauka, n = 5) yeL uye AX1-3 yakatenuka mumhepo, mvura, uye 10% gelatin (20 mm kudzika) ine (pamusoro) matunhu matatu emodal (yakaderera. , pakati, pakakwirira).), uye iwo anoenderana modal frequencies\(f_{1-3}\) (kHz), (avhareji) simba rekushanda\(\text {PTE}_{1{-}3 }\) inoshandisa magadzirirwo equation.(4) uye (pasi) ndiwo upamhi hwakazara pahafu yeukoshi hwepamusoro hwakayerwa \(\text {FWHM}_{1{-}3}\) (Hz), zvichiteerana.Ziva kuti pakurekodha PTE yakaderera, kureva kuti kana iri AX2 slope, kuyerwa kwebandwidth kunosiiwa, \(\text {FWHM}_{1}\).Iyo \(f_2\) modhi inoonekwa seyakanyanya kukodzera kuenzanisa kutsauka kwendege dzakarerekera, sezvo ichiratidzira danho repamusoro rekufambisa simba kwesimba (\(\text {PTE}_{2}\)), kusvika 99%.
Yekutanga modal dunhu: \(f_1\) haitsamire zvakanyanya parudzi rwemedia rwakaiswa, asi zvinoenderana nebevel geometry.\(f_1\) inodzikira nekudzikira kwebevel kureba (27.1, 26.2 uye 25.9 kHz yeAX1-3, zvichiteerana, mumhepo).Avhareji yedunhu \(\mavara {PTE}_{1}\) uye \(\mavara {FWHM}_{1}\) ari \(\ approx\) 81% ne230 Hz zvichiteerana.\(\text {FWHM}_{1}\) yaive yepamusoro-soro mugelatin kubva kuLancet (L, 473 Hz).Ziva kuti \(\text {FWHM}_{1}\) yeAX2 mugelatin haigone kufungidzirwa nekuda kwehushoma hwemhinduro dzefrequency dzakashumwa.
Yechipiri modal dunhu: \(f_2\) zvinoenderana nerudzi rwepaste uye bevel media.Mumhepo, mvura uye gelatin, avhareji \(f_2\) kukosha ndeye 29.1, 27.9 uye 28.5 kHz, zvichiteerana.Iyo PTE yenzvimbo ino modal yakasvikawo 99%, iyo yepamusoro-soro pakati pemapoka ese ekuyera, ine avhareji yedunhu ye84%.Avhareji yenzvimbo \(\text {FWHM}_{2}\) \(\ approx\) 910 Hz.
Yetatu modal dunhu: \(f_3\) Iyo frequency inotsamira pamhando yekuisa yepakati uye bevel.Avhareji \(f_3\) kukosha ndeye 32.0, 31.0 uye 31.3 kHz mumhepo, mvura uye gelatin, zvichiteerana.\(\text {PTE}_{3}\) ine avhareji yedunhu \(\inenge\) 74%, yakaderera pane chero dunhu.Avhareji yedunhu \(\text {FWHM}_{3}\) \(\inenge\) 1085 Hz, iri pamusoro penzvimbo yekutanga neyechipiri.
Izvi zvinotevera zvinoreva Fig.12 uye Tafura 2. The lancet (L) yakatsauka zvakanyanya (nekukosha kwepamusoro kune mazano ose, \ (p <\) 0.017) mumhepo uye mumvura (Fig. 12a), kuwana DPR yepamusoro (kusvika ku220 µm / W mumhepo). 12 uye Tafura 2. The lancet (L) yakatsauka zvakanyanya (nekukosha kwepamusoro kune mazano ose, \ (p <\) 0.017) mumhepo uye mumvura (Fig. 12a), kuwana DPR yepamusoro (kusvika ku220 µm / W mumhepo). Следующее относится к рисунку 12 и таблице 2 воздухе, так и в воде (рис. 12а), достигая самого высокого DPR . Izvi zvinotevera zvinoshanda kuMufananidzo 12 uye Tafura 2. Lancet (L) yakatsauka zvakanyanya (nekukosha kwepamusoro kune mazano ose, \ (p <\) 0.017) mumhepo uye mvura (Fig. 12a), kubudirira kwepamusoro DPR.(kusvika 220 μm/W mumhepo).Reference inoitwa Figure 12 uye Tafura 2 pazasi.柳叶刀(L) 在空气和水中（图12a）中偏转最大（对所有尖端具有高度意义，\(p<\) 0.017 经结 经结 经继继着高达220 µm/W)柳叶刀(L) ine kutsauka kwakanyanya mumhepo nemvura (图12a) (对所述尖端是对尖端是是电影,\(p<\) 0.017), uye yakawana iyo yepamusoro DPR (kusvika 220 µm/ W mumhepo). Ланцет (L) имеет наибольшее отклонение (весьма значимое для всех наконечников, \(p<\) 0,017) в воздухе и воде (рис 0 мкм/Вт в воздухе). Lancet (L) ine kutsauka kukuru (kunyanya kukosha kune mazano ose, \ (p <\) 0.017) mumhepo nemvura (Fig. 12a), inosvika pakakwirira DPR (kusvika ku220 µm / W mumhepo). Mumhepo, AX1 yaive neBL yakakwira, yakatsauka kupfuura AX2–3 (ine kukosha, \(p<\) 0.017), ukuwo AX3 (yaive neBl yakaderera) yakatsauka kupfuura AX2 neDPR ye190 µm/W. Mumhepo, AX1 yaive neBL yakakwira, yakatsauka kupfuura AX2–3 (ine kukosha, \(p<\) 0.017), ukuwo AX3 (yaive neBl yakaderera) yakatsauka kupfuura AX2 neDPR ye190 µm/W. В воздухе AX1 с более высоким BL отклонялся выше, чем AX2–3 (со значимостью \(p<\) 0,017), тогда как AX3 (с самлон , AX3) X2 с DPR 190 мкм/Вт. Mumhepo, AX1 ine BL yakakwirira yakatsauka kupfuura AX2–3 (ine kukosha \(p<\) 0.017), nepo AX3 (ine yakaderera BL) yakatsauka kupfuura AX2 neDPR 190 µm/W.在空气中，具有较高BL的AX1 偏转高于AX2-3（具有显着性，\(p<\) 0.017），而AX3（具有最D01D 10D 101D µm/W. Mumhepo, kutsauka kweAX1 ine BL yepamusoro kwakakwira kupfuura iyo yeAX2-3 (zvakakosha, \(p<\) 0.017), uye kutsauka kweAX3 (ine yakaderera BL) yakakwirira kupfuura iyo yeAX2, DPR i190. µm/W. В воздухе AX1 с более высоким BL имеет большее отклонение, чем AX2-3 (значимо, \(p<\) 0,017), тогда как AX3 (с самым BL низет) чем AX2 с DPR 190 мкм/Вт. Mumhepo, AX1 ine BL yepamusoro ine kutsauka kukuru pane AX2-3 (yakakosha, \(p<\) 0.017), nepo AX3 (ine yakaderera BL) ine kutsauka kukuru kupfuura AX2 ine DPR ye190 μm/W. Mumvura pa20 mm, hapana misiyano yakakosha (\(p>\) 0.017) yakawanikwa mukutsauka uye PTE yeAX1-3. Mumvura pa20 mm, hapana misiyano yakakosha (\(p>\) 0.017) yakawanikwa mukutsauka uye PTE yeAX1-3. В воде на глубине 20 мм достоверных различий (\(p>\) 0,017) по прогибу и ФТР для AX1–3 не обнаружено. Mumvura pakadzika kwe20 mm, misiyano yakakosha (\(p>\) 0.017) mukutsauka uye FTR yakaonekwa yeAX1-3.在20 mm 的水中，AX1-3 的挠度和PTE 没有显着差异(\(p>\) 0.017). Mune 20 mm yemvura, pakanga pasina musiyano wakakosha pakati peAX1-3 nePTE (\(p>\) 0.017). На глубине 20 мм прогиб и PTE AX1-3 существенно не отличались (\(p>\) 0,017). Pakadzika kwe20 mm kutsauka uye PTE AX1-3 haina kusiyana zvakanyanya (\(p>\) 0.017).Nhamba dzePTE mumvura (90.2-98.4%) dzaive dzakakwirira kudarika mumhepo (56-77.5%) (Fig. 12c), uye chiitiko che cavitation chakaonekwa panguva yekuedza mumvura (Fig. 13, onawo kuwedzera ruzivo).
Tip bending amplitude zviyero (zvinoreva ± standard deviation, n = 5) yeL uye AX1-3 chamfers mumhepo nemvura (kudzika 20 mm) yakaburitsa mhedzisiro yekuchinja chamfer geometry.Izvo zviyero zvinowanikwa uchishandisa inoenderera imwe frequency sinusoidal excitation.(a) Peak kutsauka (\(u_y\vec {j}\)) pa vertex, akapimwa pa (b) iwo modal frequency \(f_2\).(c) Simba rekufambisa zvakanaka (PTE, rms, %) sekuenzanisa.(4) uye (d) Deviation power factor (DPR, µm/W) yakaverengerwa sepeak deviation uye kutumira simba \(P_T\) (Wrms).
Yakajairika mimvuri yekamera yekumhanya-mhanya inoratidza kutsauka kwakazara kweiyo lancet tip (girinhi uye tsvuku ine mitsara ine madota) ye lancet (L) uye axisymmetric tip (AX1-3) mumvura (yakadzika 20mm), hafu kutenderera, drive frequency. \(f_2\) (frequency 310 kHz sampling).Mufananidzo wakatorwa wegreyscale une zviyero zve 128 × 128 pixels ine saizi yepixel ye \(\ approximate) 5 µm.Vhidhiyo inogona kuwanikwa mune rumwe ruzivo.
Nokudaro, takafananidzira kuchinja kwekukotama kwewavelength (Fig. 7) uye takaverenga kushandiswa kwemagetsi kwekufambisa kune yakajairika lanceolate, asymmetric, uye axial kusanganiswa kwechubhu kureba uye bevel (Fig. 8, 9).Symmetrical beveled geometry.Zvichienderana nezvekupedzisira, takafungidzira kuti yakanakisa tip-to-weld chinhambwe kuita 43 mm (kana \(\ approx\) 2.75\(\lambda_y\) pa29.75 kHz) sezvakaratidzwa mumufananidzo 5, uye takagadzira matatu axisymmetric bevels ane. kureba kwakasiyana kwebevel.Takazoratidza mhinduro dzavo dzenguva tichienzanisa neyakajairwa lancets mumhepo, mvura, uye 10% (w / v) ballistic gelatin (Figure 10, 11) uye takasarudza iyo yakanakisa kesi yekuenzanisa tilt deflection mode.Pakupedzisira, takayera kutsauswa kwetip nekukotama wave mumhepo uye mumvura pakadzika kwe20 mm uye tikaongorora simba rekufambisa simba (PTE, %) uye deflection power factor (DPR, µm/W) yesvikiro rakaiswa jekiseni kune imwe neimwe kurereka.rudzi (Fig. 12).
Mhedzisiro yacho inoratidza kuti kurerekera axis yejiometry inokanganisa amplitude kutsauka kweiyo tip axis.Iyo lancet yaive nepamusoro-soro curvature uye zvakare yepamusoro DPR ichienzaniswa neaxisymmetric bevel, nepo axisymmetric bevel yaive nediki zvinoreva kutsauka (Fig. 12). Iyo axi-symmetric 4 mm bevel (AX1) ine kureba kwebevel kureba, yakawaniswa yakanyanya kukosha kutsauka mumhepo (\(p <0.017\), Tafura 2), mukuenzanisa nedzimwe axi-symmetric tsono (AX2–3), asi hapana misiyano inokosha yakaonekwa, apo tsono yakaiswa mumvura. Iyo axi-symmetric 4 mm bevel (AX1) ine kureba kwebevel kureba, yakawaniswa yakanyanya kukosha kutsauka mumhepo (\(p <0.017\), Tafura 2), mukuenzanisa nedzimwe axi-symmetric tsono (AX2–3), asi hapana misiyano inokosha yakaonekwa, apo tsono yakaiswa mumvura. Осесимметричный скос 4 мм (AX1), имеющий наибольшую длину скоса, достиг статистически значимого наибольшего отклонения отклонения отклонения отклонения отклонения в 0, программу внению с другими осесимметричными иглами (AX2–3). Axisymmetric bevel 4 mm (AX1), iine kureba kwebevel kureba, yakawana kutsauka kwakakosha mumhepo (\(p <0.017\), Tafura 2) zvichienzaniswa nedzimwe axisymmetric tsono (AX2–3).asi misiyano inokosha haina kuonekwa pakuisa tsono mumvura.与其他轴对称针(AX2-3) 相比，具有最长斜角长度的轴对称4 mm 斜角(AX1) 在空气中官玲(\(p <0.017\),表2)，但当将针头放入水中时，没有观察到显着差异. Zvichienzaniswa nedzimwe axially symmetric tsono (AX2-3), ine kurebesa oblique kona ye 4 mm axially symmetrical (AX1) mumhepo, uye yakawana statistically yakakosha yakanyanya kutsauka (\(p <0.017\), Tafura 2) , asi tsono payakaiswa mumvura, hapana musiyano unokosha wakaonekwa. Осесимметричный скос 4 мм (AX1) с наибольшей длиной скоса обеспечивает статистически значимое максимальное отклонение отклонение отклонение отклонение отклонение в воздупечивает статистическа ыми иглами (AX2-3) (\(p < 0,017\), таблица 2), но существенной разницы не было. The axisymmetric slope ine kureba kwakatsetseka kwe4 mm (AX1) yakapa statistically yakakosha kutsauka kwemhepo zvichienzaniswa nemamwe axisymmetric slopes (AX2-3) (\(p <0.017\), Tafura 2), asi pakanga pasina. musiyano mukuru.inocherechedzwa kana tsono yaiswa mumvura.Nekudaro, iyo yakareba bevel kureba haina mabhenefiti ari pachena maererano nepeak tip deflection.Tichifunga izvi, zvinoitika kuti materu geometry, ayo anoferefetwa muchidzidzo ichi, ane simba guru pakutsauka kweamplitude kupfuura kureba kwemateru.Izvi zvinogona kuenderana nekukotama kuomarara, semuenzaniso, zvichienderana nechinhu chiri kubhenda uye ukobvu hwese hwetsono yekuvaka.
Muzvidzidzo zvekuedza, ukuru hweinoratidzwa flexural wave inobatwa nemiganhu yemuganhu wetip.Pakapinzwa tsono mumvura negelatin, \(\text {PTE}_{2}\) yakaenzana \(\ approx\) 95% uye \(\text {PTE}_{2}\) yakaverengera kukosha ari 73% uye 77% (\ zvinyorwa {PTE}_{1}\) uye \(\ zvinyorwa {PTE}_{3}\), zvichiteerana (Fig. 11).Izvi zvinoratidza kuti kukwidziridzwa kweacoustic simba kune yekukanda svikiro (somuenzaniso, mvura kana gelatin) inoitika pa \(f_2\).Mafambiro akafanana akaonekwa muchidzidzo chakapfuura tichishandisa zvimisikidzo zvakareruka zve41-43 kHz, apo vanyori vakaratidza ratidziro yevoltage coefficient yakabatana nemakanika modulus yepakati yakabatana.Iyo yekupinda yakadzika32 uye ma mechanic zvimiro zvetishu zvinopa mekinika mutoro patsono uye nekudaro zvinotarisirwa kupesvedzera hunhu hweUZeFNAB.Naizvozvo, resonance yekutevera algorithms senge 17, 18, 33 inogona kushandiswa kukwidziridza simba reinzwi rinounzwa kuburikidza nechinyoreso.
Bend wavelength modeling (Fig. 7) inoratidza kuti axisymmetric ine yakakwirira structural stiffness (kureva yakakwirira kukotama kuoma) pamuromo kupfuura lancet uye asymmetric bevel.Yakatorwa kubva (1) uye tichishandisa iyo inozivikanwa velocity-frequency hukama, isu tinofungidzira kukotama kuomarara kwe lancet, asymmetric uye axisymmetric matipi semateru \(\ approximate) 200, 20 uye 1500 MPa, zvichiteerana.Izvi zvinoenderana ne (\ lambda _y\) 5.3, 1.7 uye 14.2 mm pa 29.75 kHz, maererano (Fig. 7a-c).Tichifunga nezvekuchengetedzwa kwekiriniki kweiyo USeFNAB maitiro, pesvedzero yejometri pakuomarara kwebevel dhizaini inoda kuongororwa34.
Chidzidzo chezviyero zvebevel uye kureba kwechubhu (Fig. 9) yakaratidza kuti iyo yakakwana TL yemhando yeasymmetric (1.8 mm) yaive yakakwirira kupfuura yeaxisymmetric bevel (1.3 mm).Mukuwedzera, nzvimbo yekufamba inotangira kubva ku4 kusvika ku4.5 mm uye kubva pa6 kusvika ku7 mm yeasymmetric uye axisymmetric tilt, maererano (Fig. 9a, b).Iko kushanda kwekuita kwekutsvaga uku kunoratidzwa mukugadzira kushivirira, semuenzaniso, yakaderera huwandu hweyakanyanya TL inogona kureva kudiwa kwehurefu hwepamusoro.Panguva imwecheteyo, chikuva chegoho chinopa kushivirira kukuru kwesarudzo yehurefu hwemateru pane imwe nguva yakapihwa pasina kukanganisa zvakanyanya goho.
Chidzidzo chacho chinosanganisira zvinotevera zvinogumira.Kuyera kwakananga kwetsono kutsauswa uchishandisa kumucheto kwekuona uye kukurumidza-kumhanya kufungidzira (Mufananidzo 12) zvinoreva kuti isu tinongogumira kune midhiya inoonekera semhepo nemvura.Tinodawo kuratidza kuti hatina kushandisa zviedzo kuti tiedze kuenzaniswa kwekufambisa kwekufambisa uye zvakasiyana, asi takashandisa zvidzidzo zveFEM kuti tione hurefu hwakakwana hwetsono yakagadzirwa.Kubva pakuona kwezvisingakwanisi, kureba kwe lancet kubva kumucheto kusvika kune sleeve yakareba 0.4 cm kupfuura dzimwe tsono (AX1-3), ona fig.3b.Izvi zvinogona kunge zvakakanganisa mhinduro ye modal ye acicular structure.Pamusoro pezvo, chimiro uye vhoriyamu yewaveguide lead solder (ona Mufananidzo 3) inogona kukanganisa mechanical impedance yepini dhizaini, zvichikonzera kukanganisa mumagetsi impedance uye kukotama maitiro.
Chekupedzisira, takaedza nekuyedza kuti bevel geometry inokanganisa huwandu hwekutsauka muUSeFNAB.Mumamiriro ezvinhu apo iyo yakakwira deflection amplitude inogona kuve nemhedzisiro pamhedzisiro yetsono pamatishu, semuenzaniso, kucheka kunyatsoita mushure mekubaya, yakajairika lancet inogona kukurudzirwa kuUSeFNAB, sezvo ichipa yakanyanya kutsauka amplitude uchichengeta kuomarara kwakaringana. pamuromo wekugadzira.Uye zvakare, ongororo ichangoburwa yakaratidza kuti yakakura matipi deflection inogona kuwedzera biological mhedzisiro senge cavitation, iyo inogona kubatsira kukudziridza maapplication ekupindira kushoma invasive kuvhiya.Tichifunga kuti kuwedzera kwese acoustic simba kwakaratidzwa kuwedzera biopsy goho kubva kuUSeFNAB13, zvimwe zvidzidzo zvehuwandu hwegoho remuenzaniso uye mhando inodiwa kuti uongorore yakadzama yekiriniki kubatsirwa kweiyo yakadzidziswa tsono geometry.
Frable, WJ Yakanaka tsono aspiration biopsy: wongororo.Humph.Kurwara.14:9-28.https://doi.org/10.1016/s0046-8177(83)80042-2 (1983).
Nguva yekutumira: Oct-13-2022