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An extraordinary multielement apparatus of conodont Nicoraella from the Middle Triassic Luoping Biota,southwest China
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作者 Jin-yuan Huang 《China Geology》 CAS CSCD 2023年第1期183-184,共2页
Conodont animal is an extinct group of marine animals.The conodont elements and their hard skeletal remains are originally from the head region of this kind of animal,and they are considered to be functioned as“teeth... Conodont animal is an extinct group of marine animals.The conodont elements and their hard skeletal remains are originally from the head region of this kind of animal,and they are considered to be functioned as“teeth”.The“multielement apparatus”can also be called the“(conodont)apparatus”,“multimembrate(skeletal)apparatus”. 展开更多
关键词 apparatus SOUTHWEST MIDDLE
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A rigid true triaxial apparatus for analyses of deformation and failure features of deep weak rock under excavation stress paths
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作者 Xia-Ting Feng Xiaojun Yu +2 位作者 Yangyi Zhou Chengxiang Yang Feiyan Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第5期1065-1075,共11页
The squeezing scenario in deep weak rock tunnels can hinder underground construction.However,due to the limitations of test technologies at hand,the real excavation stress path cannot be mimicked in the laboratory.Thu... The squeezing scenario in deep weak rock tunnels can hinder underground construction.However,due to the limitations of test technologies at hand,the real excavation stress path cannot be mimicked in the laboratory.Thus,the large deformation mechanism of deep weak rocks still remains unclear.For this,a true triaxial apparatus(TTA)to investigate the mechanical responses of deep weak rock under excavation stress paths in field and reveal the squeezing mechanism of deep tunnels is assembled and developed at Northeastern University,China.The apparatus can perform instantaneous unloading in s3 direction based on electromagnetism technology.In addition,uniform loading and deformation measurements can be carried out based on the proposed linked interlocking clamp and antifriction device,even if the sample has a strong dilatation deformation performance.Next,a bore trepanning is designed to capture noiseless acoustic emission(AE)signals for deep weak rock at a low threshold.Finally,two tests were are conducted using this instrument to preliminarily understand the failure and deformation features of deep weak rock based on fractured marble.The results show that the complete stressestrain curves of fractured marble have the characteristics of low strengths and large deformations,and the larger deformation and the more serious failure occur when the fractured marble enters the post-peak state after excavation.The results show that the developed apparatus is likely to be applicable for deep weak rock engineering. 展开更多
关键词 True triaxial apparatus(TTA) Deep weak rock Large deformation Excavation stress path Instantaneous unloading
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A data complementary method for thunderstorm point charge localization based on atmospheric electric field apparatus array group 被引量:3
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作者 Xu Yang Hongyan Xing 《Digital Communications and Networks》 SCIE CSCD 2021年第2期170-177,共8页
Data loss or distortion causes adverse effects on the accuracy and stability of the thunderstorm point charge localization.To solve this problem,we propose a data complementary method based on the atmospheric electric... Data loss or distortion causes adverse effects on the accuracy and stability of the thunderstorm point charge localization.To solve this problem,we propose a data complementary method based on the atmospheric electric field apparatus array group.The electric field component measurement model of the atmospheric electric field apparatus is established,and the orientation parameters of the thunderstorm point charge are defined.Based on the mirror method,the thunderstorm point charge coordinates are obtained by using the potential distribution formulas.To test the validity of the basic algorithm,the electric field component measurement error and the localization accuracy are studied.Besides the azimuth angle and the elevation angle,the localization parameters also include the distance from the apparatus to the thunderstorm cloud.Based on a primary electric field apparatus,we establish the array group of apparatuses.Based on this,the data measured by each apparatus is complementarily processed to regain the thunderstorm point charge position.The results show that,compared with the radar map data,this method can accurately reflect the location of the thunderstorm point charge,and has a better localization effect.Additionally,several observation results during thunderstorm weather have been presented. 展开更多
关键词 Atmospheric electric field apparatus ARRAY Thunderstorm point charge Data complementary
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SIMULATION TEST APPARATUS FOR MARINE CORROSION 被引量:1
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作者 李言涛 侯保荣 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1999年第1期49-52,41,共5页
This paper describes the setup and working mechanism of a simulation test apparatus for marine corrosion. Experimental results showed the apparatus can basically reflect the corrosion behavior of steel in various mari... This paper describes the setup and working mechanism of a simulation test apparatus for marine corrosion. Experimental results showed the apparatus can basically reflect the corrosion behavior of steel in various marine environments, and is simple, convenient, and reliable for testing steel used for marine engineering. 展开更多
关键词 MARINE CORROSION TEST apparatus simulate
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A Breakthrough in Pressure Generation by a Kawai-Type Multi-Anvil Apparatus with Tungsten Carbide Anvils 被引量:1
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作者 Takayuki Ishii Zhaodong Liu Tomoo Katsura 《Engineering》 SCIE EI 2019年第3期434-440,共7页
Expansion of the pressure range of Kawai-type multi-anvil presses (KMAPs) with tungsten carbide (WC) anvils is called for, especially in the field of Earth science. However, no significant progress in pressure generat... Expansion of the pressure range of Kawai-type multi-anvil presses (KMAPs) with tungsten carbide (WC) anvils is called for, especially in the field of Earth science. However, no significant progress in pressure generation has been made for 40 years. Our recent studies have expanded the pressure generation of a KMAP with WC anvils to 65 GPa, which is the world record for high-pressure generation in this device and is more than 2.5 times higher than conventional pressure generation. We have also successfully generated pressures of about 50 GPa at high temperatures. This work reviews our recently developed technology for high-pressure generation. High-pressure generation at room temperature and at high temperature was attained by integration of the following techniques:① a precisely aligned guideblock system,② a high degree of hardness of the second-stage anvils,③ tapering of the second-stage anvil faces,④ a high-pressure cell consisting of materials with a high bulk modulus, and ⑤ high thermal insulation of the furnace. Our high-pressure technology will facilitate investigation of the phase stability and physical properties of materials under the conditions of the upper part of the lower mantle, and will permit the synthesis and characterization of novel materials. 展开更多
关键词 High PRESSURE Multi-anvil apparatus Tungsten carbide ANVIL Sintered diamond Lower mantle
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HT-7 Multipoint Nd Laser Thomson Scattering Apparatus 被引量:2
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作者 毛剑珊 赵君煜 +2 位作者 李亚东 谢爱根 方自深 《Plasma Science and Technology》 SCIE EI CAS CSCD 2001年第2期691-702,共12页
A compact, low cost, multipoint Thomson scattering diagnostic system for HT-7 superconducting tokamak has been in operation since 1999. Its capability of measuring electron temperatures is in the range of 200 eV to 2 ... A compact, low cost, multipoint Thomson scattering diagnostic system for HT-7 superconducting tokamak has been in operation since 1999. Its capability of measuring electron temperatures is in the range of 200 eV to 2 keV at a density of a few times IO12 cm-3, with a spatial resolution of 2.4 cm for 5 spatial points and a temporal resolution of 1 ms-1 s for 8 time points. The main components of the diagnostic system include a 20-25 J Nd: glass laser with 35 ns pulse width (8 pulses per burst), a KDP frequency-doubling unit, spherical mirrors of multipass input optical system, a wide-angle collection objective, a bandpass glass filter for reducing the stray light to zero a f/2.5 polychromator, a fiberglass collimator, a photomultiplier’s box with electronic preamplifier, high gain and high signal/noise ratio, CAMAC data acquisition and so on. The multipass optical system has been successful at increasing the quantity of scattered photons by passing the probing laser beam 10 times through the plasma under investigation. The HT7 Thomson scattering diagnostic has provided successfully the information on two-dimensional electron temperature in the plasma of HT-7 tokamak with LHCD and IBW. 展开更多
关键词 HT-7 Multipoint Nd Laser Thomson Scattering apparatus
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Endoscopic surgery for inverted papilloma with carcinoma change of lacrimal drainage apparatus and nasal cavity 被引量:2
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作者 Yin-Hung Chang Tsan-Jen Chiu Wei-Cherng Hsu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第3期582-584,共3页
Dear Sir,Iam Dr.Yin-Hung Chang from the Department of Otolaryngology,Taipei Tzu Chi Hospital,the Buddhist Tzu Chi Medical Foundation.I would like to present a case of inverted papilloma with carcinoma change of lacrim... Dear Sir,Iam Dr.Yin-Hung Chang from the Department of Otolaryngology,Taipei Tzu Chi Hospital,the Buddhist Tzu Chi Medical Foundation.I would like to present a case of inverted papilloma with carcinoma change of lacrimal drainage apparatus and nasal cavity that had been successfully treated by endoscopic surgery.Lacrimal drainage apparatus tumors are rare but 展开更多
关键词 Endoscopic surgery for inverted papilloma with carcinoma change of lacrimal drainage apparatus and nasal cavity
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MORPHOLOGICAL COMPARISON OF THE FEEDING APPARATUS OF THREE CO-OCCURRING SPECIES OF PONYFISHES (LEIOGNATHIDAE)
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作者 刘静 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1997年第3期224-226,共3页
Ponyfishes of the family Leiognathidae frequently show overlapping distribution pattems in the Indo-Pacific and South China Sea. The mouth morphology of three species of ponyfishes which feed at different lerels in th... Ponyfishes of the family Leiognathidae frequently show overlapping distribution pattems in the Indo-Pacific and South China Sea. The mouth morphology of three species of ponyfishes which feed at different lerels in the water column were compared. The species could be distinguished primarily by the mouth meropology. Gazza minuta (Bloch)feeds mainly on bethos, has the least protruding jaws; Secutor ruconius (Hamilton-Buchanan) feeds mainly on plankton, has the most protruding jaws, Leiognathus rivuatus (Temmink et Schlegel) has an intermediate deggree of jaw protrusion. This study showed that closely related species with overlapping distributions frequently exhibit morphologlcal, phpsiological or ecological differences related to the search for food, the intake of food or locomotion mode. 展开更多
关键词 Gazza minuta Leiognathus rivulatus Secutor ruconius FEEDING apparatus JAW PROTRUSION
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Numerical simulation and experimental verification of a novel double-layered split die for high-pressure apparatus used for synthesizing superhard materials
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作者 Zhuo Yi Wen-zhi Fu +3 位作者 Ming-zhe Li Rui Li Liang Zhao Li-yan Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第3期377-385,共9页
Based on the principles of massive support and lateral support, a novel double-layered split die(DLSD) for high-pressure apparatus was designed to achieve a higher pressure-bearing capacity and larger sample cavity. T... Based on the principles of massive support and lateral support, a novel double-layered split die(DLSD) for high-pressure apparatus was designed to achieve a higher pressure-bearing capacity and larger sample cavity. The stress distributions of the DLSDs with different numbers of divided blocks were investigated by the finite element method and compared with the stress distributions of the conventional belt-type die(BTD). The results show that the cylinders and first-layer supporting rings of the DLSDs have dramatically smaller stresses than those of the BTD. In addition, increasing the number of divided blocks from 4 to 10 gradually increases the stress of the cylinder but has minimal influence on the stress of the supporting rings. The pressure-bearing capacities of the DLSDs with different numbers of divided blocks, especially with fewer blocks, are all remarkably higher than the pressure-bearing capacity of the BTD. The contrast experiments were also carried out to verify the simulated results. It is concluded that the pressure-bearing capacities of the DLSDs with 4 and 8 divided blocks are 1.58 and 1.45 times greater than that of the BTD. This work is rewarding for the commercial synthesis of high-quality, large-sized superhard materials using a double-layered split high-pressure die. 展开更多
关键词 SPLIT DIE prismatic CYLINDER pressure-bearing capacity high-pressure apparatus SUPERHARD material FEM
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DEVELOPMENT OF TESTER USED IN EVALUATING UNDERWATER BREATHING APPARATUS
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作者 Mao Fanggan and Lu Shunchang (Engineers, Naval Medical Research Institute, Shanghai) 《China Ocean Engineering》 SCIE EI 1989年第3期383-383,共1页
A test set-up called hyperbaric unmanned tester has been developed to assess the safety andreliability of deep sea respirator before manned testing. The tester possesses three basic capabili-ties: First, it is to simu... A test set-up called hyperbaric unmanned tester has been developed to assess the safety andreliability of deep sea respirator before manned testing. The tester possesses three basic capabili-ties: First, it is to simulate the operational conditions of underwater breathing apparatus. Thatis, it can reproduce ambient pressure as great as that of 300 meters deep sea water and ambienttemperature ranging between 4℃ and 40℃. It is also capable of reproducing the diver’s 展开更多
关键词 AMBIENT MANNED apparatus TESTER operational HYPERBARIC BREATHING capable reproduce UNDERWATER
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DEVELOPMENT OF NEW TYPE DYNAMIC SHEAR TESTING APPARATUS OF BULK SOLID
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作者 Aixiang Wu Desheng Gu Hua Hu 《Journal of Central South University》 SCIE EI CAS 1999年第2期111-114,共4页
The functions and system structure of DSA 1 Type direct shear apparatus were described, which is noted for its various functions, advanced techniques of multi desciplines. The apparatus adopted advanced measuring syst... The functions and system structure of DSA 1 Type direct shear apparatus were described, which is noted for its various functions, advanced techniques of multi desciplines. The apparatus adopted advanced measuring system and has high accuracy of testing data. It provide a new technical measure for the study of dynamic characteristics of bulk solid. 展开更多
关键词 DYNAMIC DIRECT SHEAR apparatus structure BULK SOLID DYNAMIC characteristics
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HY369-B MODEL LASER ACUPUNCTURE APPARATUS Winner of Gold Medal atthe 38th Brussels Eureka World Fair for Invention
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《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1990年第4期319-319,共1页
The HY369-B Model Laser Acupuncture Apparatus was invented byHuang Mingrong,director and engineer of the Pingyang Laser Device Factory,Zhejiang Province. The apparatus is an integration of traditional acupuncturewith ... The HY369-B Model Laser Acupuncture Apparatus was invented byHuang Mingrong,director and engineer of the Pingyang Laser Device Factory,Zhejiang Province. The apparatus is an integration of traditional acupuncturewith laser and optic fiber technique.He-Ne laser is transmitted to acupoint lo-calities on the surface of the body,or into the depth of acupoints via optic 展开更多
关键词 ACUPOINT Acupuncture OPTIC ENGINEER director LASER apparatus transmitted instrument body
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CLINICAL OBSERVATION ON THE TREATMENT OF CERVICAL SPONDYLOSIS, SCAPULOHUMERAL PERIARTHRITIS AND LUMBAR MUSCLE STRAIN BY A MODEL FZ-1 SIMULATED TUINA (MASSAGE) APPARATUS
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作者 许能贵 顾新建 +4 位作者 曹亮明 钱海源 王善楠 易玮 闰怀士 《World Journal of Acupuncture-Moxibustion》 1997年第3期33-36,共4页
We have treated 30 cases of cervical spondylosis, 30 cases of scapulohumeral periarthritis and 30 cases of lumbar muscle strain with a Model FZ - 1 Simulated Massage Apparatus, and gained satisfactory therapeutic effe... We have treated 30 cases of cervical spondylosis, 30 cases of scapulohumeral periarthritis and 30 cases of lumbar muscle strain with a Model FZ - 1 Simulated Massage Apparatus, and gained satisfactory therapeutic effect for all cases treated. Moreover, this apparatus is applied conveniently,and has no adverse reaction. 展开更多
关键词 SIMULATED MASSAGE apparatus Cervical SPONDYLOSIS Scapulohumeral PERIARTHRITIS Lumbar muscle strain
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DEVELOPMENT OF AN APPARATUS FOR MEASURING HEAT TRANSFER PROPERTIES OF CLOTHING MATERIALS
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作者 俞建勇 赵书经 《Journal of Donghua University(English Edition)》 EI CAS 1989年第Z1期110-118,共9页
In this paper an apparatus for measuring heat transfer properties of clothing materials is re-ported.In comparison with the similar device based on constant temperature method and em-ploying a hot plate,the characteri... In this paper an apparatus for measuring heat transfer properties of clothing materials is re-ported.In comparison with the similar device based on constant temperature method and em-ploying a hot plate,the characteristics of this apparatus are as follows.(1)By using microcomputer as its testing control and data processing center,the testingfunction is strengthened,while much more information can be achieved.(2)By using numerical PID control technique supported with software,the informationabout the transient heat transfer properties of clothing materials can be obtained,while the costlowered.In this paper a brief evaluation of the apparatus is also reported.It shows that its accuracyand repeatability reaches the level of similar commercial device,so to some extent the apparatusis practical. 展开更多
关键词 CLOTHING HEAT TRANSFER test apparatus MICROCOMPUTER
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Study of ss-DNA Adsorption and Nano-mechanical Properties on Mica Substrate with Surface Forces Apparatus
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作者 Gui-Bin Shen Ya-Jing Kan +1 位作者 Min-Hua Chen Yun-Fei Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第5期91-98,共8页
Many DNA?based devices need to build stable and controllable DNA films on surfaces. However, the most com?monly used method of film characterization, namely, the probe?like microscopes which may destroy the sample and... Many DNA?based devices need to build stable and controllable DNA films on surfaces. However, the most com?monly used method of film characterization, namely, the probe?like microscopes which may destroy the sample and substrate. Surface Forces Apparatus(SFA) technique, specializing in surface interaction studies, is introduced to investigate the e ects of DNA concentration on the formation of single?stranded DNA(ss?DNA) film. The result demonstrates that 50 ng/μL is the lowest concentration that ss?DNA construct a dense layer on mica. Besides, it is also indicated that at di erent DNA concentrations, ss?DNA exhibit diverse morphology: lying flat on surface at 50 ng/μL while forming bilayer or cross?link at 100 ng/μL, and these ss?DNA structures are stable enough due to the repeatabil?ity even under the load of 15 mN/m. At the same time, an obvious adhesion force is measured:/m at 100 ng/μL, respectively, which is attributed to the ion?correlation e ect. M-6.5 mN/m at 50 ng/μL and-5.3 mNoreover, the atomic force microscopy(AFM) images reveal the entire surface is covered with wormlike ss?DNA and the measured surface roughness(1.8±0.2 nm) also matches well with the film thickness by SFA. The desorption behaviors of ss?DNA layer from mica surface occur by adding sodium salt into gap bu er, which is mainly ascribed to the decreased ion?ion cor?relation force. This paper employing SFA and AFM techniques to characterize the DNA film with flexibility and stable mechanical ability achieved by ion bridging method, is helpful to fabricate the DNA?based devices in nanoscale. 展开更多
关键词 Single-stranded DNA ADSORPTION Nano-mechanical properties Ion-correlation effect Surface forces apparatus
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Pressure calibration and sound velocity measurement to 12 GPa in multi-anvil apparatus
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作者 Wei Song Shuangming Shan +2 位作者 Qizhe Tang Chang Su Yonggang Liu 《Acta Geochimica》 EI CAS CSCD 2021年第4期525-531,共7页
We performed the pressure calibration to 12 GPa for 14/6 type(octahedron edge length/WC truncated edge length,in mm) cell assembly in DS 6 × 1400 multi-anvil apparatus by using the phase transitions in Bi(Ⅰ-Ⅱ2.... We performed the pressure calibration to 12 GPa for 14/6 type(octahedron edge length/WC truncated edge length,in mm) cell assembly in DS 6 × 1400 multi-anvil apparatus by using the phase transitions in Bi(Ⅰ-Ⅱ2.55 GPa,Ⅲ-Ⅴ 7.67 GPa) and ZnTe(LPP-HPP Ⅰ 9.6 GPa,HPP Ⅰ-Ⅱ 12.0 GPa).As verification and application,sound velocity measurements on poly crystalline Al_(2)O_(3) to 12 GPa at room temperature were conducted and the ultrasonic result is in good agreement with previous reports.It demonstrates the feasibility of performing sound velocity measurements close to the mantle transition zone pressure condition in our laboratory. 展开更多
关键词 Pressure calibration Sound velocity Multi-anvil apparatus Polycrystalline alumina
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Low Energy Positron Beam Apparatus for Near-surface Studies and Its Application
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作者 GUO Xuezhe WENG Huimin HAN Rongdian 《Chinese Physics Letters》 SCIE CAS CSCD 1992年第9期491-494,共4页
A low-energy positron beam apparatus has been designed and constructed.The beam can deliver a current of 4× 10^(4)e+/s to a target when a 7.3mCi ^(22)Na source is used.The energy range,available at present is bet... A low-energy positron beam apparatus has been designed and constructed.The beam can deliver a current of 4× 10^(4)e+/s to a target when a 7.3mCi ^(22)Na source is used.The energy range,available at present is between 25eV and 16keV.We have applied it to study initially on the dynamic process of WSix film formation and on the distribution defects produced by N^(+) ion in nickel. 展开更多
关键词 BEAM apparatus initially
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A novel anti-shock silicon etching apparatus for solving diaphragm release problems
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作者 石莎莉 陈大鹏 +3 位作者 欧毅 景玉鹏 徐秋霞 叶甜春 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期195-199,共5页
This paper presents a novel anti-shock bulk silicon etching apparatus for solving a universal problem which occurs when releasing the diaphragm (e.g.SiNx),that the diaphragm tends to be probably cracked by the impact ... This paper presents a novel anti-shock bulk silicon etching apparatus for solving a universal problem which occurs when releasing the diaphragm (e.g.SiNx),that the diaphragm tends to be probably cracked by the impact of heatinginduced bubbles,the swirling of heating-induced etchant,dithering of the hand and imbalanced etchant pressure during the wafer being taken out.Through finite element methods,the causes of the diaphragm cracking are analysed.The impact of heating-induced bubbles could be the main factor which results in the failure stress of the SiNx diaphragm and the rupture of it.In order to reduce the four potential effects on the cracking of the released diaphragm,an anti-shock bulk silicon etching apparatus is proposed for using during the last etching process of the diaphragm release.That is,the silicon wafer is first put into the regular constant temperature etching apparatus or ultrasonic plus,and when the residual bulk silicon to be etched reaches near the interface of the silicon and SiNx diaphragm,within a distance of 50-80 μm (the exact value is determined by the thickness,surface area and intensity of the released diaphragm),the wafer is taken out carefully and put into the said anti-shock silicon etching apparatus.The wafer's position is at the geometrical centre,also the centre of gravity of the etching vessel.An etchant outlet is built at the bottom.The wafer is etched continuously,and at the same time the etchant flows out of the vessel.Optionally,two symmetrically placed low-power heating resistors are put in the anti-shock silicon etching apparatus to quicken the etching process.The heating resistors' power should be low enough to avoid the swirling of the heating-induced etchant and the impact of the heating-induced bubbles on the released diaphragm.According to the experimental results,the released SiNx diaphragm thus treated is unbroken,which proves the practicality of the said anti-shock bulk silicon etching apparatus. 展开更多
关键词 anti-shock bulk silicon etching apparatus RELEASING DIAPHRAGM finite element analysis
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An enhanced underwater camera apparatus for seabed observation of megabenthic epifauna in the northern Yellow Sea
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作者 YU Nan SUN Song +4 位作者 WANG Shiwei LIU Qun ZHANG Guangtao ZHANG Fang SUN Xiaoxia 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第6期1799-1810,共12页
Seabed photographing has been applied with various underwater camera apparatuses(UCAs)for observations of megabenthic epifauna,which reveals more details than traditional sampling tools do.In this study,we improved a ... Seabed photographing has been applied with various underwater camera apparatuses(UCAs)for observations of megabenthic epifauna,which reveals more details than traditional sampling tools do.In this study,we improved a UCA named a towed underwater video-camera system(TUV system)with image processing software for seabed photographing in coastal areas up to 100 m.In May 2017,the TUV system was tested at 4 stations in the Zhangzi Island marine area in the northern Yellow Sea to investigate local megabenthic epifauna,especially brittle stars.At each station,more than 500 good seabed photographs each in area of 0.1550 m2 were obtained in just 10 min.Almost all of the epifauna larger than 1 mm could be identified from the photographs,including echinoderms,bivalves,cnidarians,and crustaceans.Three dominant brittle stars(Ophiopholis mirabilis,Ophiura sarsii vadicola,and Stegophiura sladeni)were spotted,and their abundance,disc diameter,cluster size,and coverage area were calculated and analyzed from the seabed photographs.The results show that the TUV system could be applied in coastal waters of hard sandy bottoms and could be used for quantitative investigations of megabenthic epifauna. 展开更多
关键词 seabed photography brittle stars underwater camera apparatuses(UCAs) coastal waters
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Experimental investigation on hard rock fragmentation of inserted tooth cutter using a newly designed indentation testing apparatus
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作者 Jiuqun Zou Weihao Yang +2 位作者 Tao Zhang Xiaofei Wang Min Gao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第3期459-470,共12页
This investigation aims to explore the effects of stress conditions and rock cutting rates on hard rock fragmentation through indentation tests on a newly designed triaxial testing apparatus.This apparatus was designe... This investigation aims to explore the effects of stress conditions and rock cutting rates on hard rock fragmentation through indentation tests on a newly designed triaxial testing apparatus.This apparatus was designed to realize a triaxial loading and indentation test of cylindrical specimens using inserted tooth cutter.The boreability and crushing efficiency of granite rock was investigated by analyzing the change rules of the thrusting force,penetration depth,characteristics of chippings and failure patterns.Several quantitative indexes were used to evaluate rock boreability in this investigation.The granite rock samples all had a chiselled pit and a crushed rock core.Under initial stress conditions,only flat-shape chippings were stripped from the rock surface when the thrusting force reached 20 kN.The rock cutting special energy had a close correlation with the initial stress conditions and inserted tooth shape.Moreover,a thrusting force prediction model was proposed in this paper.The contribution of this study is that for the first time the influence mechanism of the initial triaxial stress conditions on rock fragmentation is investigated using an inserted tooth and the newly designed testing apparatus.This study has a crucial importance for practical underground hard rock crushing in geoengineering. 展开更多
关键词 Hard rock indentation test Hard rock fragmentation Triaxial confined conditions New triaxial testing apparatus Inserted tooth cutter Cylindrical rock specimens
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