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Design and application of thickness measurement calibration system based on laser displacement sensor
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作者 SUN Jin YU Zijin 《Baosteel Technical Research》 CAS 2024年第2期39-46,共8页
This study aims to improve the accuracy and safety of steel plate thickness calibration.A differential noncontact thickness measurement calibration system based on laser displacement sensors was designed to address th... This study aims to improve the accuracy and safety of steel plate thickness calibration.A differential noncontact thickness measurement calibration system based on laser displacement sensors was designed to address the problems of low precision of traditional contact thickness gauges and radiation risks of radiation-based thickness gauges.First,the measurement method and measurement structure of the thickness calibration system were introduced.Then,the hardware circuit of the thickness system was established based on the STM32 core chip.Finally,the system software was designed to implement system control to filter algorithms and human-computer interaction.Experiments have proven the excellent performance of the differential noncontact thickness measurement calibration system based on laser displacement sensors,which not only considerably improves measurement accuracy but also effectively reduces safety risks during the measurement process.The system offers guiding significance and application value in the field of steel plate production and processing. 展开更多
关键词 steel plate thickness high precision measurement noncontact thickness measurement laser displace-ment sensor
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Instantaneous Creep in Face-centered Cubic Metals at Ultra- low Strain Rates by a High-resolution Strain Measurement
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作者 SHEN Junjie Ikeda Kenichi +1 位作者 Hata Satoshi Nakashima Hideharu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第6期1096-1100,共5页
Instantaneous creep in face-centered cubic metals, 5N Al(99.999%), 2N Al (99%) and 4N Cu (99.99%) with different grain sizes, was firstly investigated by sudden stress-change experiments at ultra- low strain rat... Instantaneous creep in face-centered cubic metals, 5N Al(99.999%), 2N Al (99%) and 4N Cu (99.99%) with different grain sizes, was firstly investigated by sudden stress-change experiments at ultra- low strain rates ε ≤10-10 s-1 and temperature T 〈 0.32 Tn. The experimental results indicate that the observed instantaneous creep is strongly dependent on grain size, the concentration of impurity, and stacking fault energy. Creep in high-purity aluminum, 5N Al, with a very large grain size, d 〉 1600μm, shows non-viscous behavior, and is controlled by the recovery of dislocations in the boundary of dislocation cells. On the other hand, for 5N A1 with a small grain size, d=30μm, and low-purity aluminum, 2N A1, with d8= 25μm, creep shows viscous behavior and may be related to 'low temperature grain boundary sliding'. For high-purity copper, 4N Cu, with d= 40 grn and lower stacking fault energy, creep shows a non-viscous behavior, and is controlled by the recovery process of dislocations. For all of the samples, creep shows anelastic behavior. 展开更多
关键词 face-centered cubic metals instantaneous creep ultra-low strain rate high strain resolution measurement
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Wide-Temperature-Range Dielectric Permittivity Measurement under High Pressure
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作者 Zhen Yuan Jin-Long Zhu +4 位作者 Shao-Min Feng Chang-Chun Wang Li-Juan Wang Qing-Qing Liu Chang-Qing Jin 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第4期13-17,共5页
Two measurement systems are developed for in-situ dielectric property measurement under high pressure in a wide-temperature range from 77K to 1273 K. The high-temperature system ranging from room temperature up to 127... Two measurement systems are developed for in-situ dielectric property measurement under high pressure in a wide-temperature range from 77K to 1273 K. The high-temperature system ranging from room temperature up to 1273K is equipped with a hexahedron anvils press, while the low-temperature system ranging from liquid nitrogen temperature to normal condition is equipped using the piston cylinder setup with a specially designed sample chamber. Using these configurations, the dielectric property measurement of ferroelectrie BaTiO3 and multiferroie Tm0.5Gd0.5MnO3 compounds are demonstrated, which proves the validity of the systems through the tuning of the polarization and phase transition boundary by high pressure. These two systems will be equally applicable to a wide variety of electronic and transport property measurements of insulators, semiconductors, as well as battery materials. 展开更多
关键词 der Wide-Temperature-Range Dielectric Permittivity measurement under high Pressure BTO
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High Precision Tungsten Isotope Measurements by MC-ICPMS
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作者 MEI Qingfeng YANG Jinhui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期273-274,共2页
1 Introduction The short-lived 182Hf-182W system is generally acknowledged as the best chronometer of metal-silicate segregation that occurred during the early evolution of asteroids and terrestrial planets due to its... 1 Introduction The short-lived 182Hf-182W system is generally acknowledged as the best chronometer of metal-silicate segregation that occurred during the early evolution of asteroids and terrestrial planets due to its following properties:(1)Hf-W fractionation commonly occurs during metal-silicate differentiation;(2)Both Hf and W are highly refractory elements,therefore most bulk 展开更多
关键词 high Precision Tungsten Isotope measurements by MC-ICPMS HF MC
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A fast emittance measurement unit for high intensity DC beam
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作者 张艾霖 任海涛 +7 位作者 彭士香 张滔 徐源 张景丰 温佳美 武文斌 郭之虞 陈佳洱 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期446-449,共4页
A combined unit, which has the ability to measure the current and emittance of the high intensity direct current(DC)ion beam, is developed at Peking University(PKU). It is a multi-slit single-wire(MSSW)-type bea... A combined unit, which has the ability to measure the current and emittance of the high intensity direct current(DC)ion beam, is developed at Peking University(PKU). It is a multi-slit single-wire(MSSW)-type beam emittance meter combined with a water-cooled Faraday Cup, named high intensity beam emittance measurement unit-6(HIBEMU-6). It takes about 15 seconds to complete one measurement of the beam current and its emittance. The emittance of a 50-mA@50-kV DC proton beam is measured. 展开更多
关键词 emittance measurement high intensity DC beam MSSW
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Establishment and Error Analysis of Model of Interference Fringe Contrast for Laser Tracing Measurement Optical System
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作者 Hongfang Chen Mengyang Sun +3 位作者 Yinglun Ma Liang Tang Yu Wang Huixu Song 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第4期37-49,共13页
A method was proposed to analyze the influences of the non-ideal spectroscopic performance of optical components and orientation errors of a laser tracing measurement optical system on the tracing measurement performa... A method was proposed to analyze the influences of the non-ideal spectroscopic performance of optical components and orientation errors of a laser tracing measurement optical system on the tracing measurement performance.A comprehensive model of the interference fringe contrast based on the laser tracing system s measurement principle was established in this study.Simulation results based on ZEMAX verified the model.According to the simulation results,the placement angle of the analyzer had a direct influence on the interference fringe contrast.When the angle of the polarized light to the analyzer’s transmission axis increased from 65°to 85°,each contrast of the four-way interference fringes decreased from 0.9996 to 0.3528,the interference fringe contrast is decreased by 65%.Under the split ratio of beam splitters in the interference part(BS 1)of 5∶5,when the splitting ratio of BS 2 changed from 2∶8 to 8∶2,the fringe contrast of the interference signals received by the photodetectors increased,but the injection light intensity onto the PSD reflected by BS 2 decreased.The significant influence of the tracing performance was verified by the experiments.When splitting ratio of BS 2 increased,the contrast of the interference fringes increased.Due to the weakening of the incident light intensity of the PSD caused by the change of BS 2 splitting ratio,the response time of the tracing system is increased by 23.7 ms.As a result,the tracing performance of the laser tracing measurement optical system was degraded.An important theoretical basis was provided to evaluate and improve the accuracy and reliability of laser tracing measurement systems. 展开更多
关键词 interference fringe contrast laser tracing measurement high precision measurement ZEMAX.
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Cold Atom Cloud with High Optical Depth Measured with Large Duty Cycle
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作者 张骏 顾振杰 +2 位作者 钱鹏 韩枝光 陈洁菲 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期96-99,共4页
We present a cold atom system with a dark-line two-dimensional magneto-optical trap, to increase the atomic density by suppressing the atomic radiation pressure. Optical depth (OD) and duty cycle are used to evaluat... We present a cold atom system with a dark-line two-dimensional magneto-optical trap, to increase the atomic density by suppressing the atomic radiation pressure. Optical depth (OD) and duty cycle are used to evaluate the system performance. We demonstrate a 100% increase in OD with the dark line, and obtain an ultrahigh OD of 264 with 10% for the duty cycle. Also, with an efficient dark line region, the OD could maintain above i00 with duty cycle as high as 30%. The cold atomic ensemble with an ultrahigh OD with a 10%-30% duty cycle is particularly advantageous in quantum i^formation processing and communication. 展开更多
关键词 Cold Atom Cloud with high Optical Depth Measured with Large Duty Cycle MOT OD
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Design of High Precision Horizontal Control Network for Large-Scale Hydropower Project
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作者 ZHANG Zhenglu LUO Changlin +1 位作者 DENG Yong XIE Niansheng 《Geo-Spatial Information Science》 2006年第4期235-239,共5页
A new solution of combination network of GPS and high precise distance measurements with EDM is proposed. Meanwhile, it’s inadvisable only using GPS network without distance measurements. Three schemes: terrestrial n... A new solution of combination network of GPS and high precise distance measurements with EDM is proposed. Meanwhile, it’s inadvisable only using GPS network without distance measurements. Three schemes: terrestrial network, GPS network and combination network are discussed for horizontal control network design of Xiangjiaba Dam in view of precision, reliability, coordinate and outlay in detail. 展开更多
关键词 large-scale hydropower project terrestrial network GPS network combination network of GPS and high precise distance measurements with EDM
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The Magnetic Anisotropy and Complete Phase Diagram of CuFeO2 Measured in a Pulsed High Magnetic Field up to 75 T
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作者 左华坤 时丽然 +6 位作者 夏正才 黄俊伟 陈柏蓉 金昭 魏蒙 欧阳钟文 成刚 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第4期130-133,共4页
The magnetization behavior of a CuFeO2 single crystal grown by the floating zone technique is investigated with a pulsed high magnetic field. We observe a series of field-induced multi-step-like transitions with hyste... The magnetization behavior of a CuFeO2 single crystal grown by the floating zone technique is investigated with a pulsed high magnetic field. We observe a series of field-induced multi-step-like transitions with hysteresis, of which the critical magnetic fields are temperature-dependent and show anisotropy. By using a pulsed high magnetic field up to 75 T, the magnetization behavior shows that the critical transition magnetic fields of spin- flip/flop shift to lower field regions with an increase in temperature. According to the magnetization curves, a complete magnetic phase diagram is depicted. 展开更多
关键词 The Magnetic Anisotropy and Complete Phase Diagram of CuFeO2 Measured in a Pulsed high Magnetic Field up to 75 T AFM
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Long-term decay of the water pressure in the osmotic tensiometer
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作者 Hengshuo Liu Harianto Rahardjo +1 位作者 Hejun Du Abdul Halim Hamdany 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第3期738-746,共9页
Matric suction is an important state variable required for the assessment of unsaturated soil properties.Tensiometers are commonly used for direct matric suction measurement but have a limited measuring range up to 90... Matric suction is an important state variable required for the assessment of unsaturated soil properties.Tensiometers are commonly used for direct matric suction measurement but have a limited measuring range up to 90 kPa due to the cavitation problem.Osmotic tensiometer(OT)can improve the measuring range of tensiometers by increasing the osmotic pressure of water to avoid the cavitation.However,the long-term water pressure decay that appeared in OTs caused a gradual decrease in their measuring range.In this study,crosslinked poly(acrylamide-co-acrylic acid)potassium salt(PAM-co-PAAK)was used for the preparation of OTs(five in total)to explore the mechanism of water pressure decay of OTs.The maximum water pressure in the OT versus the volume fraction of polymer filled in the OT was described based on the Flory-Huggins polymer theories and validated using WP4C dewpoint hygrometer.The long-term pressure decay of OT-1,OT-2,and OT-3 was observed for 130 d and constant pressures were found for OT-1 and OT-2,indicating that the pressure decay of OT was mainly caused by the stress relaxation of the polymer hydrogels,and standard linear solid(SLS)rheological model was appropriate to fit the decay data.For OT-1,OT-2 and OT-3,the theoretical osmotic pressure that was calculated based on the mass of retrieved polymer from OTs after 130-d pressure observation was higher than the actual osmotic pressure as observed,indicating that polymer leakage cannot explain the pressure decay of the OT.The ultravioletevisible(UVevisible)spectrophotometry examined the change in polymer concentrations in the water containers of OT-4 and OT-5 and demonstrated that there was no increase in polymer leakage during the period of pressure decay of OT-4 and OT-5.As a result,the pressure decay of OT was not caused by polymer leakage.The results of this research suggested that the viscoelastic properties of polymers should be taken into consideration in further OT development. 展开更多
关键词 high suction measurement Osmotic tensiometers Long-term pressure decay Polymer leakage Viscoelasticity of polymers
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Effects of Main Cultivation Factors on Rapeseed Oil Yield
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作者 赵继献 杜才富 +2 位作者 任廷波 程国平 王仙萍 《Agricultural Science & Technology》 CAS 2014年第3期386-391,411,共7页
[Objective] This study aimed to analyze the influence of six cultivation fac- tors: sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount, potash fertilizer amount and boron fertilizer a... [Objective] This study aimed to analyze the influence of six cultivation fac- tors: sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount, potash fertilizer amount and boron fertilizer amount on seed oil yield of Brassica napus. [Method] Statistical analysis was carried out based on the data from previous studies and our work. [Result] Oil yield shared a negative correlation with sowing date, a parabolic relationship with plant density mostly, parabolic rela- tionships with amount of applied nitrogen fertilizer and amount of applied boron fer- tilizer, straight-line relationships with amount of applied phosphate fertilizer and amount of applied potash fertilizer. The average amount of applied nitrogen fertilizer required to obtain the highest oil yield was 185.18 kg/hm2 for high-oil rape varieties (with oil content above 44.00%), and under this condition, the average oil yield of low-oil rape varieties (with oil content below 42.00%) was 1 247.84 kg/hm2, while that of high-oil rape varieties was 1 442.60 kg/hm2, which was 15.61% more than the former. The average amount of applied nitrogen fertilizer required to obtain the highest oil yield for lower-oil rape varieties was 286.28 kg/hm2, and under this con- dition, the average oil yield of the low-oil rape varieties was 1 350.57 kg/hm2, while that of the high-oil varieties was 6.81% higher than it. There was a significant neg- ative correlation between rapeseed oil yield and the amount of applied nitrogen fer- tilizer to obtain the highest oil yield (0.980 0). The optimum amount of applied ni- trogen, phosphate, potash and boron fertilizer were 187.5-195, 187.5-195, 105-120, 135-150 and 15-22.5 kg/hm2 for high-oil B. napus varieties. [Conclusion] This study determined the influence of sowing date, plant density and amount of applied nitro- gen fertilizer on oil yield of B. napus, and proposed an optimum cultivation pattern for high-oil varieties. 展开更多
关键词 Brassica napus L. Cultivation factor Oil yield INFLUENCE Cultivation measures to keep high quality
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Elemental and proximate analysis of coal by x-ray fluorescence assisted laser-induced breakdown spectroscopy 被引量:4
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作者 Zhihui TIAN Xiaolin LI +9 位作者 Gang WANG Lei ZHANG Jiaxuan LI Shuqing WANG Yu BAI Wanfei ZHANG Han YUE Xiaofei MA Wangbao YIN Suotang JIA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第8期55-63,共9页
Although laser-induced breakdown spectroscopy(LIBS),as a fast on-line analysis technology,has great potential and competitiveness in the analysis of chemical composition and proximate analysis results of coal in therm... Although laser-induced breakdown spectroscopy(LIBS),as a fast on-line analysis technology,has great potential and competitiveness in the analysis of chemical composition and proximate analysis results of coal in thermal power plants,the measurement repeatability of LIBS needs to be further improved due to the difficulty in controlling the stability of the generated plasmas at present.In this paper,we propose a novel x-ray fluorescence(XRF) assisted LIBS method for high repeatability analysis of coal quality,which not only inherits the ability of LIBS to directly analyze organic elements such as C and H in coal,but also uses XRF to make up for the lack of stability of LIBS in determining other inorganic ash-forming elements.With the combination of elemental lines in LIBS and XRF spectra,the principal component analysis and the partial least squares are used to establish the prediction model and perform multi-elemental and proximate analysis of coal.Quantitative analysis results show that the relative standard deviation(RSD) of C is 0.15%,the RSDs of other elements are less than 4%,and the standard deviations of calorific value,ash content,sulfur content and volatile matter are 0.11 MJ kg,0.17%,0.79% and 0.41%respectively,indicating that the method has good repeatability in determination of coal quality.This work is helpful to accelerate the development of LIBS in the field of rapid measurement of coal entering the power plant and on-line monitoring of coal entering the furnace. 展开更多
关键词 laser-induced breakdown spectroscopy(LIBS) x-ray fluorescence spectrometry(XRF) high repeatability measurement spectral calibration instability analysis
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Research on key techniques of expendable conductivity temperature depth measuring system 被引量:5
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作者 CHEN Guangyuan DU Libin +3 位作者 HE Haijing LEI Zhuo ZHANG Qisheng WU Chengxuan 《Instrumentation》 2015年第2期18-27,共10页
This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put ... This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put forward.According to the real needs of XCTD,conductivity sensor with high sensitivity is designed by principle of electromagnetic induce,the ocean conductivity from induced electromotive force has been calculated.Adding temperature correction circuit would help to reduce error of conductivity measurement because of sharply changing temperature.Advanced temperature measuring circuit of high precision and the constant current source is used to weaken effect of self-heating of resistance and fluctuation of the source.On respect of remote data transmission,LVDS is a good choice for the purpose of guarantee the quality of data transmitted and the transmission distance is reaching to thousand meters in the seawater.Modular programming method is also brought into this research aimed at improve the stability,reliability and maintainability of the whole measuring system.In February,2015,the trials in South China Sea demonstrate that the developed XCTD realize effective measurement at a speed of 6 knots and detection depth at 800 m.The consistency coefficient of the acquired data is greater than 0.99 and the success rate of probe launching is above 90%. 展开更多
关键词 expendable device XCTD conductivity sensor high precision temperature measuring circuit remote data transmission
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Large excavations and their effect on displacement of land boundaries 被引量:1
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作者 Jan Nemcik Naj Aziz 《International Journal of Mining Science and Technology》 SCIE EI 2012年第5期633-637,共5页
A study to estimate land surface movement caused by large surface excavations in sedimentary strata is presented.In stratified or jointed strata the stress relief driven movement adjacent to large excavations can be s... A study to estimate land surface movement caused by large surface excavations in sedimentary strata is presented.In stratified or jointed strata the stress relief driven movement adjacent to large excavations can be significantly larger than expected.High lateral stresses measured in Australia and other places around the world indicate that the ratio of horizontal to vertical stress has been particularly high at shallow depths.The in situ strata is in compression and during excavation,stress is relieved towards the opening causing strata movement.Large excavations such as,open cut mines or highway cuttings,can initiate an extensive horizontal slide of surface layers towards the excavation.These ground movements can be damaging to surface structures such as water storage dams and large buildings.Based on stress measurements at shallow depths in Australian coal mines the study presented here calculates and models the extent of potential ground movement along the bedding surface adjacent to large excavations and provides a new prediction tool of land movement at the excavation boundary that can benefit the geotechnical practitioners in the mining industry. 展开更多
关键词 Stress measurements high lateral stress Lateral stress relief Lateral displacement of bedded strata Stability of large excavations
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Shock temperature and reflectivity of precompressed H2O up to 350 GPa:Approaching the interior of planets
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作者 Zhi-Yu He Hua Shu +10 位作者 Xiu-Guang Huang Qi-Li Zhang Guo Jia Fan Zhang Yu-Chun Tu Jun-Yue Wang Jun-Jian Ye Zhi-Yong Xie Zhi-Heng Fang Wen-Bing Pei Si-Zu Fu 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第12期405-412,共8页
Using a combination of static precompression and laser-driven shock compression, shock temperature and reflectivity of H2O have been measured up to 350 GPa and 2.1×10~4 K. Here, two calibration standards were app... Using a combination of static precompression and laser-driven shock compression, shock temperature and reflectivity of H2O have been measured up to 350 GPa and 2.1×10~4 K. Here, two calibration standards were applied to enhance temperature measurement reliability. Additionally, in temperature calculations, the discrepancy in reflectivity between active probe beam wavelength and self-emission wavelength has been taken into account to improve the data’s precision.Precompressed water’s temperature–pressure data are in very good agreement with our quantum molecular dynamics model,suggesting a superionic conductor of H2O in the icy planets’ deep interior. A sluggish slope gradually approaching Dulong–Petit limit at high temperature was found at a specific heat capacity. Also, high reflectivity and conductivity were observed at the same state. By analyzing the temperature–pressure diagram, reflectivity, conductivity and specific heat comprehensively at conditions simulating the interior of planets in this work, we found that as the pressure rises, a change in ionization appears; it is supposedly attributed to energetics of bond-breaking in the H2O as it transforms from a bonded molecular fluid to an ionic state. Such molecular dissociation in H2O is associated with the conducting transition because the dissociated hydrogen atoms contribute to electrical properties. 展开更多
关键词 high temperature measurement equation of state of water laser-driven shock diamond anvil cell
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High-throughput measurements of ciprofloxacin, clomipramine and fexofenadine hydrochlorides with an 8-channel electrical titrator
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作者 Xuzhi Zhang Qianqian Yang +4 位作者 Xuchang Zhang Pingping Wang Zhihui Hao Jun Zhao Keming Qu 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第9期1391-1394,共4页
High-throughput measurements of ciprofloxacin, clomipramine and fexofenadine hydrochlorides were performed by employing an automatic 8-channel electrical titrator. Silver nitrate (AgNO3) and sodium tetraphenylborate... High-throughput measurements of ciprofloxacin, clomipramine and fexofenadine hydrochlorides were performed by employing an automatic 8-channel electrical titrator. Silver nitrate (AgNO3) and sodium tetraphenylborate (NaTPB) were used as titrants. When AgNO3 was used for measuring the drugs in pure form, recoveries were 97.6%-102.0% with RSD values ≤1.0%; for measuring them in pharmaceutical formulations, recoveries were 96.6%-99.1% with RSD values ≤1.0%. Batch samples of eight could be measured simultaneously and maximally 30 measurements per minute could be completed. When NaTPB was used for measuring the drugs in pure form, the recoveries were 96.8%-102.6% with RSD values 〈0.8%; for measuring them in pharmaceutical formulations, the recoveries were 97.5%-102.7% with RSD values ≤0.9%. For all analyses, no auxiliary devices or chemicals were needed and there was no requirement for changing or cleaning working electrodes between measurements. The efficiency, accuracy and precision of the proposed method make it an alternative for routine quality control analyses. 展开更多
关键词 Eight-channel electrical titrator Ciprofloxacin hydrochloride Clomipramine hydrochloride Fexofenadine hydrochloride high throughput measurement Pharmaceutical analysis
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Refractive index measurement of dielectric samples using highly focused radially polarized light(Invited Paper)
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作者 Guadalupe López-Morales Victor-Manuel Rico-Botero +1 位作者 Rafael Espinosa-Luna Qiwen Zhan 《Chinese Optics Letters》 SCIE EI CAS CSCD 2017年第3期12-15,共4页
In this Letter, a refractive index measurement of a dielectric sample using highly focused radially polarized light is reported. Through imaging analysis of the optical field at the pupil plane of a high numerical ape... In this Letter, a refractive index measurement of a dielectric sample using highly focused radially polarized light is reported. Through imaging analysis of the optical field at the pupil plane of a high numerical aperture (NA) objective lens reflected by the sample under study, the Brewster angle is found. Employing a high NA objective lens allows the measurement of multiple angles of incidence from 0° to 64° in a single shot. The refractive index of the sample is estimated using the measured Brewster angle. The experimental results are compared with the theoretical images computed with the Fresnel theory, and a good agreement is obtained. 展开更多
关键词 high Refractive index measurement of dielectric samples using highly focused radially polarized light
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Review of femtosecond laser fabricated optical fiber high temperature sensors [Invited] 被引量:2
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作者 Dong-Ning Wang 《Chinese Optics Letters》 SCIE EI CAS CSCD 2021年第9期23-28,共6页
The femtosecond laser has been an efficient tool for optical fiber high temperature sensor construction.Here,we review the progress of optical fiber high temperature sensors based on femtosecond laser fabricated fiber... The femtosecond laser has been an efficient tool for optical fiber high temperature sensor construction.Here,we review the progress of optical fiber high temperature sensors based on femtosecond laser fabricated fiber gratings and various types of fiber in-line interferometers in silica fibers and sapphire fibers. 展开更多
关键词 optical fiber sensors femtosecond laser micromachining high temperature measurement
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On-board measurement of particle numbers and their size distribution from a light-duty diesel vehicle:Influences of VSP and altitude 被引量:12
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作者 Jia Liu Yunshan Ge +6 位作者 Xin Wang Lijun Hao Jianwei Tan Zihang Peng Chuanzhen Zhang Huiming Gong Ying Huang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第7期238-248,共11页
In this study,the particle size-resolved distribution from a China-3 certificated light-duty diesel vehicle was measured by using a portable emission measurement system(PEMS).In order to examine the influences of ve... In this study,the particle size-resolved distribution from a China-3 certificated light-duty diesel vehicle was measured by using a portable emission measurement system(PEMS).In order to examine the influences of vehicle specific power(VSP) and high-altitude operation,measurements were conducted at 8 constant speeds,which ranged from 10 to 80 km/hr at10 km/hr intervals,and two different high altitudes,namely 2200 and 3200 m.The results demonstrated that the numbers of particles in all size ranges decreased significantly as VSP increased when the test vehicle was running at lower speeds(〈 20 km/hr),while at a moderate speed(between 30 and 60 km/hr),the particle number was statistically insensitive to increase VSP.Under high-speed cruising conditions,the numbers of ultrafine particles and PM2.5were insensitive to changes in VSP,but the numbers of nanoparticles and PM10 surged considerably.An increase in the operational altitude of the test vehicle resulted in increased particle number emissions at low and high driving speeds;however,particle numbers obtained at moderate speeds decreased as altitude rose.When the test vehicle was running at moderate speeds,particle numbers measured at the two altitudes were very close,except for comparatively higher number concentrations of nanoparticles measured at 2200 m. 展开更多
关键词 On-board measurement Particle number Size distribution Diesel VSP high altitude
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The nitritation performance of biofilm reactor for treating domestic wastewater under high dissolved oxygen 被引量:7
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作者 Zhaoming Zheng Zebing Li +5 位作者 Jing Ma Jia Du Guanghui Chen Wei Bian Jun Li Baihang Zhao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第4期267-274,共8页
The objective of this study was to investigate the nitritation performance in a biofilm reactor for treating domestic wastewater.The reactor was operated in continuous feed mode from phases 1 to 3.The dissolved oxygen... The objective of this study was to investigate the nitritation performance in a biofilm reactor for treating domestic wastewater.The reactor was operated in continuous feed mode from phases 1 to 3.The dissolved oxygen(DO)was controlled at 3.5–7 mg/L throughout the experiment.The biofilm reactor showed excellent nitritation performance after the inoculation of nitrifying sludge,with the hydraulic retention time being reduced from 24 to 7 hr.Above 90%nitrite accumulation ratio(NAR)was maintained in phase 1.Afterwards,nitratation occurred with the low NH4^+–N concentration in the reactor.The improvement of NH4^+–N concentration to 20–35 mg/L had a limited effect on the recovery of nitritation.However,nitritation recovered rapidly when sequencing batch feed mode was adopted in phase 4,with the effluent NH4^+-N concentration above 7 mg/L.The improvement of ammonia oxidizing bacteria(AOB)activity and the combined inhibition effect of free ammonia(FA)and free nitrous acid(FNA)on the nitrite oxidizing bacteria(NOB)were two key factors for the rapid recovery of nitritation.Sludge activity was obtained in batch tests.The results of batch tests had a good relationship with the long term operation performance of the biofilm reactor. 展开更多
关键词 Nitritation high dissolved oxygen Domestic wastewater Biofilm reactor Control measures
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