An optimized transducer prototype with a sandwich structure vibrated longitudinally is proposed for a transmitter in acoustic logging, especially in acoustic logging while drilling, 5y taking account of drilling envir...An optimized transducer prototype with a sandwich structure vibrated longitudinally is proposed for a transmitter in acoustic logging, especially in acoustic logging while drilling, 5y taking account of drilling environments with high temperature and pressure, as well as strong collar drilling vibration during the drilling process. Aimed to improve the transmitting performance, numerical and experimental studies for the transducer optimization are conducted. The impact of location and length of the piezoelectric stack on resonance characteristics arid effective electromeehanical coupling coefficient is calculated and analyzed. Admittance and transmitting performance of the proposed transducer are measured in laboratory experiments, and the results are compared with simulated ones. It is shown that the newly proposed transducer has higher transmitting performance with lower resonance frequencies. This work provides theoretical and experimental bases for transducer designing and acoustic wave measurements in acoustic logging, especially in acoustic logging while drilling.展开更多
In the present paper, the effects of moxibustion on the immune organs, on the multiplication reactivity of the splenic lymphocyte and the reactivity to the IL - 2, and on the transmitters in brain tissues of the mice ...In the present paper, the effects of moxibustion on the immune organs, on the multiplication reactivity of the splenic lymphocyte and the reactivity to the IL - 2, and on the transmitters in brain tissues of the mice with "yang deficiency" were studied. 30 mice were randomly divided into three groups: the normal group, the peng deficiency control group and the moxibustion treated group. Our study found out that in the mice of yang deficienly, the atrophy of the immunt organs was prevented, the reactivity of the splenocyte and the reactivity to IL - 2 were heightened, the amounts of the DA, NE and E in brain were increased significantly after moxibustion on the Point Shengshu. It can be held that moxibustion may protect the immune organs and regulate the immunity of the mouse with yang deficienly, and the effects may be contributed to the increase of the nervous transmitters in the brain.展开更多
An Ion Cyclotron Range of Frequency （ICRF） system with a radio frequency （RF） power of 4×1.5 MW was developed for the Experimental Advanced Superconducting Tokamak （EAST）. High RF power transmitters were de...An Ion Cyclotron Range of Frequency （ICRF） system with a radio frequency （RF） power of 4×1.5 MW was developed for the Experimental Advanced Superconducting Tokamak （EAST）. High RF power transmitters were designed as a part of the research and development （R^D） for an ICRF system with long pulse operation at megawatt levels in a frequency range of 25 MHz to 70 MHz. Studies presented in this paper cover the following parts of the high power transmitter： the three staged high power amplifier, which is composed of a 5 kW wide- band solid state amplifier, a 100 kW tetrode drive stage amplifier and a 1.5 MW tetrode final stage amplifier, and the DC high voltage power supply （HVPS）. Based on engineering design and static examinations, the RF transmitters were tested using a matched dummy load where an RF output power of 1.5 MW was achieved. The transmitters provide 6 MW RF power in primary phase and will reach a level up to 12 MW after a later upgrade. The transmitters performed successfully in stable operations in EAST and HT-7 devices. Up to 1.8 MW of RF power was injected into plasmas in EAST ICRF heating experiments during the 2010 autumn campaign and plasma performance was greatly improved.展开更多
A novel sutureless surgical technique has been successfully used to implant acoustic transmitters in relatively large rainbow trout Oncorhynchus mykiss with a tag-to-body-ratio of 0.88%. This study examined the same t...A novel sutureless surgical technique has been successfully used to implant acoustic transmitters in relatively large rainbow trout Oncorhynchus mykiss with a tag-to-body-ratio of 0.88%. This study examined the same technique in smaller rainbow trout in two, 12-week trials comparing both sutured and sutureless surgical techniques. In the first trial using a tag-to-body-ratio of 1.9% ± 0.04%, tag retention was only 16.6% in fish without sutures, which was significantly lower than the 83.3% retention with sutured incisions. Similarly, in the second trial with a tag-to-body-ratio of 3.2% ± 0.03%, tag retention was 55.5% without sutures, which was significantly lower than the 90.0% retention using sutures. Mortality was not significantly different between treatments in either trial. The results of this study indicate that sutures must be used during surgeries to implant acoustic transmitters in relatively smaller fish with tag-to-body-ratios at or above 1.9%.展开更多
With the rapid development of science and technology, radio and television are becoming more and more popular. In addition, the continuous improvement of people's spiritual and cultural enthusiasm puts forward hig...With the rapid development of science and technology, radio and television are becoming more and more popular. In addition, the continuous improvement of people's spiritual and cultural enthusiasm puts forward higher requirements for radio and television. In order to ensure signal coverage, most radio and television stations choose high mountains. There are some problems and shortcomings when starting the mountain station. The integrity, integrity and reliability of radio station facilities and equipment depend on the security of transmissions and broadcasts. In order to ensure the safety and high-quality transmission of broadcast signals, the daily safety management of equipment in the computer room is very important.展开更多
Real-time water-medium endoscopic images can assist doctors in performing operations such as tissue cleaning and nucleus pulpous removal.During medical operating procedures,it is inevitable that tissue particles,debri...Real-time water-medium endoscopic images can assist doctors in performing operations such as tissue cleaning and nucleus pulpous removal.During medical operating procedures,it is inevitable that tissue particles,debris and other contaminants will be suspended within the viewing area,resulting in blurred images and the loss of surface details in biological tissues.Currently,few studies have focused on enhancing such endoscopic images.This paper proposes a water-medium endoscopic image processing method based on dual transmittance in accordance with the imaging characteristics of spinal endoscopy.By establishing an underwater imaging model for spinal endoscopy,we estimate the transmittance of the endoscopic images based on the boundary constraints and local image contrast.The two transmittances are then fused and combined with transmittance maps and ambient light estimations to restore the images before attenuation,ultimately enhancing the details and texture of the images.Experiments comparing classical image enhancement algorithms demonstrate that the proposed algorithm could effectively improve the quality of spinal endoscopic images.展开更多
We synthesized tungsten-doped vanadium dioxide(W-VO_(2))particles via a one-step hydrothermal method,followed by their integration with antimony-doped tin oxide(ATO)nanoparticles to formulate a composite coating.Subse...We synthesized tungsten-doped vanadium dioxide(W-VO_(2))particles via a one-step hydrothermal method,followed by their integration with antimony-doped tin oxide(ATO)nanoparticles to formulate a composite coating.Subsequently,the VO_(2)/ATO composite coating was fabricated through a spin-coating process.The impact of varying W-VO_(2) content and coating thickness on the performance of the composite coatings was systematically investigated by employing X-ray diffraction,particle size distribution analysis,spectrometry,and other pertinent test methodologies.Our findings revealed that an escalation in both W-VO_(2) content and coating thickness retained high transmittance in the near-infrared band at lower temperatures.However,as the temperature increased,a notable reduction in transmittance in the near-infrared band was observed,alongside a slight decrease in transmittance within the visible band.Remarkably,when the W-VO_(2) content reached 5%and the coating thickness was 1253 nm,the transmittance of the composite coating surpassed 80%.Furthermore,the heat insulation effect achieved a remarkable 10.0℃increase.Consequently,the synthesized composite coating demonstrates significant potential for smart glass applications,particularly in the realm of heat-insulating glass.展开更多
The Malkmus band model has been widely used in remote sensing and climate studies. However, its accuracy is not high. To solve this problem, a modified Malkmus band model was proposed by introducing a correction item....The Malkmus band model has been widely used in remote sensing and climate studies. However, its accuracy is not high. To solve this problem, a modified Malkmus band model was proposed by introducing a correction item. The HITRAN (High-resolution TRANsmission) 2008 database and the atmospheric models provided by the Air Force Geophysics Laboratory (AFGL) were used to calculate the molecular transmittances. By fitting the calculated transmittances to those by MODTRAN (MODerate resolution atmospheric TRANsmission) package with the least-squares method, the fitting coefficients of the correction item were obtained under different atmosphere models. The experimental results show that the root mean square errors (RMSE) of the modified model are significantly less than that of the traditional Malkmus band model by 1-2 orders of magnitude. In addition, the modified method is suitable for different atmospheric models and molecules.展开更多
We developed a novel cement evaluation logging tool,named the azimuthally acoustic bond tool（AABT）,which uses a phased-arc array transmitter with azimuthal detection capability.We combined numerical simulations and ...We developed a novel cement evaluation logging tool,named the azimuthally acoustic bond tool（AABT）,which uses a phased-arc array transmitter with azimuthal detection capability.We combined numerical simulations and field tests to verify the AABT tool.The numerical simulation results showed that the radiation direction of the subarray corresponding to the maximum amplitude of the first arrival matches the azimuth of the channeling when it is behind the casing.With larger channeling size in the circumferential direction,the amplitude difference of the casing wave at different azimuths becomes more evident.The test results showed that the AABT can accurately locate the casing collars and evaluate the cement bond quality with azimuthal resolution at the casing-cement interface,and can visualize the size,depth,and azimuth of channeling.In the case of good casingcement bonding,the AABT can further evaluate the cement bond quality at the cementformation interface with azimuthal resolution by using the amplitude map and the velocity of the formation wave.展开更多
[Objective] To explore a method for the rapid determination of protein con- tent in grains of Panicum miliaceum L. [Method] The near infrared transmittance spec- troscopy （NITS） was used to build the mathematical mo...[Objective] To explore a method for the rapid determination of protein con- tent in grains of Panicum miliaceum L. [Method] The near infrared transmittance spec- troscopy （NITS） was used to build the mathematical models for the quantitative analy- sis of protein content in the grains. Four combinations of treatment that first derivative and second derivative were respectively combined with partial least squares （PLS） and modified partial least squares （MPLS） were set to compare their effects on the original transmission spectrum. [Result] The predicting effects of the 4 combinations were similar. The optimal combination was first derivative with MPLS, in which the average determination coefficient of validation （RSQ） was 0.880 6, correlation coeffi- cient of cross validation （1-VR） was 0.857 0, standard error of calibration （SEC） was 0.342 4, standard error of cross validation （SECV） was 0.375 1, and the standard er- ror of prediction （SEP） was 0.454. [Conclusion] The constructed NITS model is a rapid way for the determination of protein content in grains of P. miliaceum.展开更多
2.5 Gbit/s monolithic integrated circuits （ICs） for optical fiber transmitter and receiver in 0.35 μm CMOS （complementary metal-oxide-semiconductor transistor） process are presented. The transmitter, which includ...2.5 Gbit/s monolithic integrated circuits （ICs） for optical fiber transmitter and receiver in 0.35 μm CMOS （complementary metal-oxide-semiconductor transistor） process are presented. The transmitter, which includes a 4： 1 multiplexer and a laser diode driver （LDD）, has four 622 Mbit/s random signals as its inputs and gets a 2.5 Gbit/s driving signal as its output; the receiver detects a 2.5 Gbit/s random signal and gets four 622 Mbit/s signals at the output. The main circuits include a trans-impedance amplifier （TIA）, a limiting amplifier, a clock and data recovery （CDR） unit, and a 1： 4 demultiplexer （DEMUX）. Test results prove the logic functions of the transmitter to be right, and the 10% to 90% rise and fall times of transmitter＇s output data eye diagram are 211.1 ps and 200 ps, respectively. The sensitivity of the receiver is measured to be better than 20 mV. The root mean square jitter of the DEMUX＇s output data is 15.6 ps and that of the clock after 1： 4 frequency dividing is 1.9 ps. Two chips are both applicable to 2.5 Gbit/s optical fiber communication systems.展开更多
A 2.4GHz ASK transmitter suitable for a low power wireless capsule endoscope system is presented. A mixer-based frequency up-conversion transmitter architecture is employed to achieve a high data rate. A pseudodiffere...A 2.4GHz ASK transmitter suitable for a low power wireless capsule endoscope system is presented. A mixer-based frequency up-conversion transmitter architecture is employed to achieve a high data rate. A pseudodifferential stacked class-A power amplifier using the current reuse technique is proposed to save power. The transmitter mainly includes two parts： a 20MHz ASK modulator based on a constant amplitude phase lock loop （PLL） and a direct up-conversion RF circuit. This design, implemented in a TSMC 0.25μm CMOS process, achieves a - 23. 217dBm output power with a data rate of 1Mbps and dissipates 3.17mA of current with a single 2.5V power supply.展开更多
背景:选择合适的陶瓷材料对口腔全瓷美学修复尤为重要。在口腔修复体美学性能研究中,多使用色差值和透光性作为评价指标,影响全瓷修复体色差和透光性的因素主要有陶瓷材料的种类、色调、厚度、加工工艺以及基牙颜色和粘接剂等。目的:探...背景:选择合适的陶瓷材料对口腔全瓷美学修复尤为重要。在口腔修复体美学性能研究中,多使用色差值和透光性作为评价指标,影响全瓷修复体色差和透光性的因素主要有陶瓷材料的种类、色调、厚度、加工工艺以及基牙颜色和粘接剂等。目的:探究材料种类及厚度对全瓷修复体美学性能的影响。方法:选取各类可切削陶瓷中6种代表性的材料(常规氧化锆ZR-ST、树脂基陶瓷RC、高透氧化锆ZR-TT、白榴石增强玻璃陶瓷LE、二硅酸锂玻璃陶瓷LD及长石质瓷FP),每种材料分别制备成0.8,1.0,1.5 mm厚的10.0 mm×12.5 mm长方体陶瓷试件,进行对应的表面处理后与树脂试件(代表基牙)粘接制成陶瓷-树脂复合体试件,测算粘接前后的CIEL^(*)a^(*)b^(*)、色差值ΔE及透光率值。结果与结论:①当基牙厚度未达到无限光学厚度时,陶瓷材料的种类和厚度共同影响修复体的颜色和透光率值。当陶瓷试件厚度不超过1.0 mm时,与树脂片粘接后的颜色普遍向蓝红趋近;当陶瓷试件厚度为1.5 mm时,与树脂片粘接后的颜色普遍向蓝绿趋近,提示在全瓷修复体比色时可通过颜色预补偿优化美学匹配。②除厚度1.5 mm ZR-ST陶瓷试件外,粘接后各组陶瓷试件与树脂片之间的色差值ΔE均低于5,0.8 mm ZR-ST陶瓷试件与树脂片之间的色差值ΔE接近3,1.0 mm ZR-TT陶瓷试件与树脂片之间的色差值ΔE小于3,提示在微创修复过程中,若患牙透光率不高且美学修复空间不足、对材料强度要求高时,ZR-TT和ZR-ST陶瓷可能是潜在的选择。③陶瓷试件的透光率值在粘接后降低,并随陶瓷厚度的增加显著降低。RC陶瓷试件的透光率值高,粘接后与树脂片之间的色差值ΔE接近3,光学性能出色。展开更多
The infrared transmittance and emissivity of heat-insulating coatings pigmented with various structural particles were studied using Kubelka-Munk theory and Mie theory. The primary design purpose was to obtain the low...The infrared transmittance and emissivity of heat-insulating coatings pigmented with various structural particles were studied using Kubelka-Munk theory and Mie theory. The primary design purpose was to obtain the low transmittance and low emissivity coatings to reduce the heat transfer by thermal radiation for high-temperature applications. In the case of silica coating layers constituted with various structural titania particles （solid, hollow, and core-shell spherical）, the dependence of transmittance and emissivity of the coating layer on the particle structure and the layer thickness was investigated and optimized. The results indicate that the coating pigmented with core-shell titania particles exhibits a lower infrared transmittance and a lower emissivity value than that with other structural particles and is suitable to radiative heat-insulating applications.展开更多
[Objective] The aim of this study was to establish a reversed phase high-performance liquid chromatography（RP-HPLC）method for the content determination of Co-Q10.[Method] The RP-HPLC method was used to detect the Co...[Objective] The aim of this study was to establish a reversed phase high-performance liquid chromatography（RP-HPLC）method for the content determination of Co-Q10.[Method] The RP-HPLC method was used to detect the Co-Q10,and the ultraviolet spectro-photometry was used to analyze the daily change of transmittance of Co-Q10.[Result] By using RP-HPLC,Co-Q10 had a good linear relationship between 40-300 μg/ml（r=0.999 9）.The limit of detection was 0.4 ng and the average recovery was 97.44%（n=3）.The system suitability of HP-HPLC was good,and the average recovery and precision results could meet the needs of assay.[Conclusion] This method was convenient,accurate and reproducible and could be used in quality control of Co-Q10.However,when it operates,light should be evaded.展开更多
Aluminum-doped zinc oxide (AZO) thin films were deposited on sapphire (002) and glass substrates by two different sputtering techniques radio frequency magnetron cosputtering of AZO and ZnO targets and sputtering of a...Aluminum-doped zinc oxide (AZO) thin films were deposited on sapphire (002) and glass substrates by two different sputtering techniques radio frequency magnetron cosputtering of AZO and ZnO targets and sputtering of an AZO target. The dependence of the photoluminescence (PL) and transmittance properties of the AZO films deposited by cosputtering and sputtering on the AZO/ZnO target power ratio, R and the O2/Ar flow ratio, r were investigated, respectively. Only a deep level emission peak appears in the PL spectra of cosputtered AZO films whereas both UV emission and deep level emission peaks are observed in the PL spectra of sputtered AZO films. The absorption edges in the transmittance spectra of the AZO films shift to the lower wavelength region as R and r increase. Effects of crystallinity, surface roughness, PL on the transmittance of the AZO films were also explained using the X-ray diffraction (XRD), atomic force microscopy (AFM), and PL analysis results.展开更多
Electron beam（EB） irradiation experiments on Au/ITO and ITO/Au/ITO multilayer thin films are reported.The structure and the optical-electrical properties of the samples were investigated by X-ray diffraction,atomic ...Electron beam（EB） irradiation experiments on Au/ITO and ITO/Au/ITO multilayer thin films are reported.The structure and the optical-electrical properties of the samples were investigated by X-ray diffraction,atomic force microscopy, four-point probe resistivity measurement system, and UV–vis-NIR double beam spectrometer, respectively. Those results show that the EB irradiation has the effects of improving the crystalline of samples, widening the optical band gap of both thin films, reducing the sheet resistance,and improving the transmittance of samples.展开更多
A time-domain electromagnetic transmitter（TDET） with great power and large current was designed by using a closed-loop phase shifting control strategy. A clamping voltage source circuit was applied in this system to...A time-domain electromagnetic transmitter（TDET） with great power and large current was designed by using a closed-loop phase shifting control strategy. A clamping voltage source circuit was applied in this system to improve the falling edge of emission current and shorten the turn-off time. The simulated results showed that this TDET exhibited the advantages including a large current, strong capability for rapid turn-off, stably output voltage, preferably dynamic performance, a widely adjustable range in transmitting voltage, accurate measurement precision.展开更多
BACKGROUND:The mechanisms underlying heat stroke(HS)-induced hippocampal injury remain unclear.This study aimed to evaluate the HS-induced metabonomics of hippocampal and cerebellar transmitters.METHODS:The HS model w...BACKGROUND:The mechanisms underlying heat stroke(HS)-induced hippocampal injury remain unclear.This study aimed to evaluate the HS-induced metabonomics of hippocampal and cerebellar transmitters.METHODS:The HS model was established with male Sprague-Dawley rats subjected to heat exposure of up to 42℃ at a humidity of(55.0±5.0)%.The hippocampal and cerebellar transmitters and metabolites of rats were tested via ultra-high-performance liquid chromatography–mass spectrometry(UPLC-MS/MS).The primary transmitters and metabolites were identified by principal component analysis(PCA)and orthogonal partial least square-discriminant analysis(OPLS-DA).The major metabolic pathways for HS were selected after enrichment.The brain injury was evaluated by histological tests.RESULTS:HS induced hippocampal and cerebellar injuries in rats.HS upregulated the protein levels of hippocampal glutamate,glutamine,gamma-aminobutyric acid,L-tryptophan(Trp),5-hydroxy-indoleacetic acid,and kynurenine;however,it downregulated asparagine,tryptamine,5-hydroxytryptophan,melatonin,3,4-dihydroxyphenylalanine(L-DOPA),and vanillylmandelic acid.HS also sharply elevated the protein levels of cerebellar methionine and Trp,and decreased the levels of serotonin,L-alanine,L-asparagine,L-aspartate,cysteine,norepinephrine,spermine,spermidine,and tyrosine.Hippocampal glutamate,monoamine transmitters,cerebellar aspartate acid,and catecholamine transmitters’metabolic pathways were identified as the main metablic pathways in HS.CONCLUSION:The hippocampus and cerebellum were injured in rats with HS,possibly induced the disorder of hippocampal glutamate and serotonin metabolism,cerebellar aspartate acid and catecholamine transmitter metabolism,and related metabolic pathways.展开更多
A parameterized transmittance model （PTR） for ozone and water vapor monochromatic transmittance calculation in the solar-to-near-infrared spectrum 0.3-4 pm with a spectral resolution of 5 cm-1 was developed based on...A parameterized transmittance model （PTR） for ozone and water vapor monochromatic transmittance calculation in the solar-to-near-infrared spectrum 0.3-4 pm with a spectral resolution of 5 cm-1 was developed based on the transmittance data calculated by Moderate-resolution Transmittance model （MOD- TRAN）. Polynomial equations were derived to represent the transmittance as functions of path length and airmass for every wavelength based on the least-squares method. Comparisons between the transmittances calculated using PTR and MODTRAN were made, using the results of MODTRAN as a reference. Rela- tive root-mean-square error （RMSre） was 0.823% for ozone transmittance. RMSre values were 8.84~ and 3.48~ for water vapor transmittance ranges of 1-1 x 10-is and 1-1x 10-3, respectively. In addition, the Stratospheric Aerosol and Gas Experiment II （SAGEII） ozone profiles and University of Wyoming （UWYO） water vapor profiles were applied to validate the applicability of PTR model. RMSre was 0.437~ for ozone transmittance. RMSre values were 8.89~ and 2.43% for water vapor transmittance ranges of 1-1~10-is and 1-1~ 10-6, respectively. Furthermore, the optical depth profiles calculated using the PTR model were compared to the results of MODTRAN. Absolute RMS errors （RMSab） for ozone optical depths were within 0.0055 and 0.0523 for water vapor at all of the tested altitudes. Finally, the comparison between the solar heating rate calculated from the transmittance of PTR and Line-by-Line radiative transfer model （LBLRTM） was performed, showing a maximum deviation of 0.238 K d-1 （6% of the corresponding solar heating rate calculated using LBLRTM）. In the troposphere all of the deviations were within 0.08 K d-1. The computational speed of PTR model is nearly two orders of magnitude faster than that of MODTRAN.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 41474160 and 11304347
文摘An optimized transducer prototype with a sandwich structure vibrated longitudinally is proposed for a transmitter in acoustic logging, especially in acoustic logging while drilling, 5y taking account of drilling environments with high temperature and pressure, as well as strong collar drilling vibration during the drilling process. Aimed to improve the transmitting performance, numerical and experimental studies for the transducer optimization are conducted. The impact of location and length of the piezoelectric stack on resonance characteristics arid effective electromeehanical coupling coefficient is calculated and analyzed. Admittance and transmitting performance of the proposed transducer are measured in laboratory experiments, and the results are compared with simulated ones. It is shown that the newly proposed transducer has higher transmitting performance with lower resonance frequencies. This work provides theoretical and experimental bases for transducer designing and acoustic wave measurements in acoustic logging, especially in acoustic logging while drilling.
文摘In the present paper, the effects of moxibustion on the immune organs, on the multiplication reactivity of the splenic lymphocyte and the reactivity to the IL - 2, and on the transmitters in brain tissues of the mice with "yang deficiency" were studied. 30 mice were randomly divided into three groups: the normal group, the peng deficiency control group and the moxibustion treated group. Our study found out that in the mice of yang deficienly, the atrophy of the immunt organs was prevented, the reactivity of the splenocyte and the reactivity to IL - 2 were heightened, the amounts of the DA, NE and E in brain were increased significantly after moxibustion on the Point Shengshu. It can be held that moxibustion may protect the immune organs and regulate the immunity of the mouse with yang deficienly, and the effects may be contributed to the increase of the nervous transmitters in the brain.
基金supported by National Magnetic Confinement Fusion Science Program of China (No.2010GB110000)partly by Knowledge Innovation Program of the Chinese Academy of Sciences (No.Y05FCQ1126)partly supported by the Japan Society for the Promotion of Science-Chinese Academy of Sciences (JSPS-CAS) Core University Program on Plasma Physics and Nuclear Fusion
文摘An Ion Cyclotron Range of Frequency （ICRF） system with a radio frequency （RF） power of 4×1.5 MW was developed for the Experimental Advanced Superconducting Tokamak （EAST）. High RF power transmitters were designed as a part of the research and development （R^D） for an ICRF system with long pulse operation at megawatt levels in a frequency range of 25 MHz to 70 MHz. Studies presented in this paper cover the following parts of the high power transmitter： the three staged high power amplifier, which is composed of a 5 kW wide- band solid state amplifier, a 100 kW tetrode drive stage amplifier and a 1.5 MW tetrode final stage amplifier, and the DC high voltage power supply （HVPS）. Based on engineering design and static examinations, the RF transmitters were tested using a matched dummy load where an RF output power of 1.5 MW was achieved. The transmitters provide 6 MW RF power in primary phase and will reach a level up to 12 MW after a later upgrade. The transmitters performed successfully in stable operations in EAST and HT-7 devices. Up to 1.8 MW of RF power was injected into plasmas in EAST ICRF heating experiments during the 2010 autumn campaign and plasma performance was greatly improved.
文摘A novel sutureless surgical technique has been successfully used to implant acoustic transmitters in relatively large rainbow trout Oncorhynchus mykiss with a tag-to-body-ratio of 0.88%. This study examined the same technique in smaller rainbow trout in two, 12-week trials comparing both sutured and sutureless surgical techniques. In the first trial using a tag-to-body-ratio of 1.9% ± 0.04%, tag retention was only 16.6% in fish without sutures, which was significantly lower than the 83.3% retention with sutured incisions. Similarly, in the second trial with a tag-to-body-ratio of 3.2% ± 0.03%, tag retention was 55.5% without sutures, which was significantly lower than the 90.0% retention using sutures. Mortality was not significantly different between treatments in either trial. The results of this study indicate that sutures must be used during surgeries to implant acoustic transmitters in relatively smaller fish with tag-to-body-ratios at or above 1.9%.
文摘With the rapid development of science and technology, radio and television are becoming more and more popular. In addition, the continuous improvement of people's spiritual and cultural enthusiasm puts forward higher requirements for radio and television. In order to ensure signal coverage, most radio and television stations choose high mountains. There are some problems and shortcomings when starting the mountain station. The integrity, integrity and reliability of radio station facilities and equipment depend on the security of transmissions and broadcasts. In order to ensure the safety and high-quality transmission of broadcast signals, the daily safety management of equipment in the computer room is very important.
文摘Real-time water-medium endoscopic images can assist doctors in performing operations such as tissue cleaning and nucleus pulpous removal.During medical operating procedures,it is inevitable that tissue particles,debris and other contaminants will be suspended within the viewing area,resulting in blurred images and the loss of surface details in biological tissues.Currently,few studies have focused on enhancing such endoscopic images.This paper proposes a water-medium endoscopic image processing method based on dual transmittance in accordance with the imaging characteristics of spinal endoscopy.By establishing an underwater imaging model for spinal endoscopy,we estimate the transmittance of the endoscopic images based on the boundary constraints and local image contrast.The two transmittances are then fused and combined with transmittance maps and ambient light estimations to restore the images before attenuation,ultimately enhancing the details and texture of the images.Experiments comparing classical image enhancement algorithms demonstrate that the proposed algorithm could effectively improve the quality of spinal endoscopic images.
基金Funded by Beijing Municipal Science&Technology Commission,Administrative Commission of Zhongguancun Science Park(No.Z221100006722022)。
文摘We synthesized tungsten-doped vanadium dioxide(W-VO_(2))particles via a one-step hydrothermal method,followed by their integration with antimony-doped tin oxide(ATO)nanoparticles to formulate a composite coating.Subsequently,the VO_(2)/ATO composite coating was fabricated through a spin-coating process.The impact of varying W-VO_(2) content and coating thickness on the performance of the composite coatings was systematically investigated by employing X-ray diffraction,particle size distribution analysis,spectrometry,and other pertinent test methodologies.Our findings revealed that an escalation in both W-VO_(2) content and coating thickness retained high transmittance in the near-infrared band at lower temperatures.However,as the temperature increased,a notable reduction in transmittance in the near-infrared band was observed,alongside a slight decrease in transmittance within the visible band.Remarkably,when the W-VO_(2) content reached 5%and the coating thickness was 1253 nm,the transmittance of the composite coating surpassed 80%.Furthermore,the heat insulation effect achieved a remarkable 10.0℃increase.Consequently,the synthesized composite coating demonstrates significant potential for smart glass applications,particularly in the realm of heat-insulating glass.
基金Projects(U1231105,41404013)supported by the National Natural Science Foundation of ChinaProject(2012AA121301)supported by the National Hi-tech Research and Development Program of China
文摘The Malkmus band model has been widely used in remote sensing and climate studies. However, its accuracy is not high. To solve this problem, a modified Malkmus band model was proposed by introducing a correction item. The HITRAN (High-resolution TRANsmission) 2008 database and the atmospheric models provided by the Air Force Geophysics Laboratory (AFGL) were used to calculate the molecular transmittances. By fitting the calculated transmittances to those by MODTRAN (MODerate resolution atmospheric TRANsmission) package with the least-squares method, the fitting coefficients of the correction item were obtained under different atmosphere models. The experimental results show that the root mean square errors (RMSE) of the modified model are significantly less than that of the traditional Malkmus band model by 1-2 orders of magnitude. In addition, the modified method is suitable for different atmospheric models and molecules.
基金supported by the National Natural Science Foundation of China(Nos.11204380,11374371,61102102,and11134011)National Science and Technology Major Project(No.2011ZX05020-009)+1 种基金China National Petroleum Corporation(Nos.2014B-4011,2014D-4105,and 2014A-3912)PetroChina Innovation Foundation(No.2014D-5006-0307)
文摘We developed a novel cement evaluation logging tool,named the azimuthally acoustic bond tool（AABT）,which uses a phased-arc array transmitter with azimuthal detection capability.We combined numerical simulations and field tests to verify the AABT tool.The numerical simulation results showed that the radiation direction of the subarray corresponding to the maximum amplitude of the first arrival matches the azimuth of the channeling when it is behind the casing.With larger channeling size in the circumferential direction,the amplitude difference of the casing wave at different azimuths becomes more evident.The test results showed that the AABT can accurately locate the casing collars and evaluate the cement bond quality with azimuthal resolution at the casing-cement interface,and can visualize the size,depth,and azimuth of channeling.In the case of good casingcement bonding,the AABT can further evaluate the cement bond quality at the cementformation interface with azimuthal resolution by using the amplitude map and the velocity of the formation wave.
基金Supported by the National Key Technology R&D Program of China (2006BAD02B07)the National Mordern Agricultural Industry System of China(CARS-07-12.5-A12)~~
文摘[Objective] To explore a method for the rapid determination of protein con- tent in grains of Panicum miliaceum L. [Method] The near infrared transmittance spec- troscopy （NITS） was used to build the mathematical models for the quantitative analy- sis of protein content in the grains. Four combinations of treatment that first derivative and second derivative were respectively combined with partial least squares （PLS） and modified partial least squares （MPLS） were set to compare their effects on the original transmission spectrum. [Result] The predicting effects of the 4 combinations were similar. The optimal combination was first derivative with MPLS, in which the average determination coefficient of validation （RSQ） was 0.880 6, correlation coeffi- cient of cross validation （1-VR） was 0.857 0, standard error of calibration （SEC） was 0.342 4, standard error of cross validation （SECV） was 0.375 1, and the standard er- ror of prediction （SEP） was 0.454. [Conclusion] The constructed NITS model is a rapid way for the determination of protein content in grains of P. miliaceum.
基金The National High Technology Research and Develop-ment Program of China (863 Program) (No.2001AA312010).
文摘2.5 Gbit/s monolithic integrated circuits （ICs） for optical fiber transmitter and receiver in 0.35 μm CMOS （complementary metal-oxide-semiconductor transistor） process are presented. The transmitter, which includes a 4： 1 multiplexer and a laser diode driver （LDD）, has four 622 Mbit/s random signals as its inputs and gets a 2.5 Gbit/s driving signal as its output; the receiver detects a 2.5 Gbit/s random signal and gets four 622 Mbit/s signals at the output. The main circuits include a trans-impedance amplifier （TIA）, a limiting amplifier, a clock and data recovery （CDR） unit, and a 1： 4 demultiplexer （DEMUX）. Test results prove the logic functions of the transmitter to be right, and the 10% to 90% rise and fall times of transmitter＇s output data eye diagram are 211.1 ps and 200 ps, respectively. The sensitivity of the receiver is measured to be better than 20 mV. The root mean square jitter of the DEMUX＇s output data is 15.6 ps and that of the clock after 1： 4 frequency dividing is 1.9 ps. Two chips are both applicable to 2.5 Gbit/s optical fiber communication systems.
文摘A 2.4GHz ASK transmitter suitable for a low power wireless capsule endoscope system is presented. A mixer-based frequency up-conversion transmitter architecture is employed to achieve a high data rate. A pseudodifferential stacked class-A power amplifier using the current reuse technique is proposed to save power. The transmitter mainly includes two parts： a 20MHz ASK modulator based on a constant amplitude phase lock loop （PLL） and a direct up-conversion RF circuit. This design, implemented in a TSMC 0.25μm CMOS process, achieves a - 23. 217dBm output power with a data rate of 1Mbps and dissipates 3.17mA of current with a single 2.5V power supply.
文摘背景:选择合适的陶瓷材料对口腔全瓷美学修复尤为重要。在口腔修复体美学性能研究中,多使用色差值和透光性作为评价指标,影响全瓷修复体色差和透光性的因素主要有陶瓷材料的种类、色调、厚度、加工工艺以及基牙颜色和粘接剂等。目的:探究材料种类及厚度对全瓷修复体美学性能的影响。方法:选取各类可切削陶瓷中6种代表性的材料(常规氧化锆ZR-ST、树脂基陶瓷RC、高透氧化锆ZR-TT、白榴石增强玻璃陶瓷LE、二硅酸锂玻璃陶瓷LD及长石质瓷FP),每种材料分别制备成0.8,1.0,1.5 mm厚的10.0 mm×12.5 mm长方体陶瓷试件,进行对应的表面处理后与树脂试件(代表基牙)粘接制成陶瓷-树脂复合体试件,测算粘接前后的CIEL^(*)a^(*)b^(*)、色差值ΔE及透光率值。结果与结论:①当基牙厚度未达到无限光学厚度时,陶瓷材料的种类和厚度共同影响修复体的颜色和透光率值。当陶瓷试件厚度不超过1.0 mm时,与树脂片粘接后的颜色普遍向蓝红趋近;当陶瓷试件厚度为1.5 mm时,与树脂片粘接后的颜色普遍向蓝绿趋近,提示在全瓷修复体比色时可通过颜色预补偿优化美学匹配。②除厚度1.5 mm ZR-ST陶瓷试件外,粘接后各组陶瓷试件与树脂片之间的色差值ΔE均低于5,0.8 mm ZR-ST陶瓷试件与树脂片之间的色差值ΔE接近3,1.0 mm ZR-TT陶瓷试件与树脂片之间的色差值ΔE小于3,提示在微创修复过程中,若患牙透光率不高且美学修复空间不足、对材料强度要求高时,ZR-TT和ZR-ST陶瓷可能是潜在的选择。③陶瓷试件的透光率值在粘接后降低,并随陶瓷厚度的增加显著降低。RC陶瓷试件的透光率值高,粘接后与树脂片之间的色差值ΔE接近3,光学性能出色。
文摘The infrared transmittance and emissivity of heat-insulating coatings pigmented with various structural particles were studied using Kubelka-Munk theory and Mie theory. The primary design purpose was to obtain the low transmittance and low emissivity coatings to reduce the heat transfer by thermal radiation for high-temperature applications. In the case of silica coating layers constituted with various structural titania particles （solid, hollow, and core-shell spherical）, the dependence of transmittance and emissivity of the coating layer on the particle structure and the layer thickness was investigated and optimized. The results indicate that the coating pigmented with core-shell titania particles exhibits a lower infrared transmittance and a lower emissivity value than that with other structural particles and is suitable to radiative heat-insulating applications.
基金Supported by Special Institutional Fund of Sichuan Agricultural University(06070904)~~
文摘[Objective] The aim of this study was to establish a reversed phase high-performance liquid chromatography（RP-HPLC）method for the content determination of Co-Q10.[Method] The RP-HPLC method was used to detect the Co-Q10,and the ultraviolet spectro-photometry was used to analyze the daily change of transmittance of Co-Q10.[Result] By using RP-HPLC,Co-Q10 had a good linear relationship between 40-300 μg/ml（r=0.999 9）.The limit of detection was 0.4 ng and the average recovery was 97.44%（n=3）.The system suitability of HP-HPLC was good,and the average recovery and precision results could meet the needs of assay.[Conclusion] This method was convenient,accurate and reproducible and could be used in quality control of Co-Q10.However,when it operates,light should be evaded.
文摘Aluminum-doped zinc oxide (AZO) thin films were deposited on sapphire (002) and glass substrates by two different sputtering techniques radio frequency magnetron cosputtering of AZO and ZnO targets and sputtering of an AZO target. The dependence of the photoluminescence (PL) and transmittance properties of the AZO films deposited by cosputtering and sputtering on the AZO/ZnO target power ratio, R and the O2/Ar flow ratio, r were investigated, respectively. Only a deep level emission peak appears in the PL spectra of cosputtered AZO films whereas both UV emission and deep level emission peaks are observed in the PL spectra of sputtered AZO films. The absorption edges in the transmittance spectra of the AZO films shift to the lower wavelength region as R and r increase. Effects of crystallinity, surface roughness, PL on the transmittance of the AZO films were also explained using the X-ray diffraction (XRD), atomic force microscopy (AFM), and PL analysis results.
基金supported financially by the National Key Research and Development Program of China (No. 2016YFB1102303)the National Basic Research Program of China (973 Program) (No. 2015CB352001)the National Natural Science Foundation of China(No. 61378060)
文摘Electron beam（EB） irradiation experiments on Au/ITO and ITO/Au/ITO multilayer thin films are reported.The structure and the optical-electrical properties of the samples were investigated by X-ray diffraction,atomic force microscopy, four-point probe resistivity measurement system, and UV–vis-NIR double beam spectrometer, respectively. Those results show that the EB irradiation has the effects of improving the crystalline of samples, widening the optical band gap of both thin films, reducing the sheet resistance,and improving the transmittance of samples.
基金Supported by the National Natural Science Foundation of China(51277189)the Chongqing Education Committee Science and Technology Research Projects(KJ1401208)
文摘A time-domain electromagnetic transmitter（TDET） with great power and large current was designed by using a closed-loop phase shifting control strategy. A clamping voltage source circuit was applied in this system to improve the falling edge of emission current and shorten the turn-off time. The simulated results showed that this TDET exhibited the advantages including a large current, strong capability for rapid turn-off, stably output voltage, preferably dynamic performance, a widely adjustable range in transmitting voltage, accurate measurement precision.
基金supported by the grants from Zhejiang Provincial Natural Science Foundation(LGF19H150004)Zhejiang Provincial Medical Science and Technology project(2022RC258)。
文摘BACKGROUND:The mechanisms underlying heat stroke(HS)-induced hippocampal injury remain unclear.This study aimed to evaluate the HS-induced metabonomics of hippocampal and cerebellar transmitters.METHODS:The HS model was established with male Sprague-Dawley rats subjected to heat exposure of up to 42℃ at a humidity of(55.0±5.0)%.The hippocampal and cerebellar transmitters and metabolites of rats were tested via ultra-high-performance liquid chromatography–mass spectrometry(UPLC-MS/MS).The primary transmitters and metabolites were identified by principal component analysis(PCA)and orthogonal partial least square-discriminant analysis(OPLS-DA).The major metabolic pathways for HS were selected after enrichment.The brain injury was evaluated by histological tests.RESULTS:HS induced hippocampal and cerebellar injuries in rats.HS upregulated the protein levels of hippocampal glutamate,glutamine,gamma-aminobutyric acid,L-tryptophan(Trp),5-hydroxy-indoleacetic acid,and kynurenine;however,it downregulated asparagine,tryptamine,5-hydroxytryptophan,melatonin,3,4-dihydroxyphenylalanine(L-DOPA),and vanillylmandelic acid.HS also sharply elevated the protein levels of cerebellar methionine and Trp,and decreased the levels of serotonin,L-alanine,L-asparagine,L-aspartate,cysteine,norepinephrine,spermine,spermidine,and tyrosine.Hippocampal glutamate,monoamine transmitters,cerebellar aspartate acid,and catecholamine transmitters’metabolic pathways were identified as the main metablic pathways in HS.CONCLUSION:The hippocampus and cerebellum were injured in rats with HS,possibly induced the disorder of hippocampal glutamate and serotonin metabolism,cerebellar aspartate acid and catecholamine transmitter metabolism,and related metabolic pathways.
基金supported by the National Basic Research Program of China (Grant No.2011CB403401)the National Natural Sciences Foundation of China (Grant No. 41175029)
文摘A parameterized transmittance model （PTR） for ozone and water vapor monochromatic transmittance calculation in the solar-to-near-infrared spectrum 0.3-4 pm with a spectral resolution of 5 cm-1 was developed based on the transmittance data calculated by Moderate-resolution Transmittance model （MOD- TRAN）. Polynomial equations were derived to represent the transmittance as functions of path length and airmass for every wavelength based on the least-squares method. Comparisons between the transmittances calculated using PTR and MODTRAN were made, using the results of MODTRAN as a reference. Rela- tive root-mean-square error （RMSre） was 0.823% for ozone transmittance. RMSre values were 8.84~ and 3.48~ for water vapor transmittance ranges of 1-1 x 10-is and 1-1x 10-3, respectively. In addition, the Stratospheric Aerosol and Gas Experiment II （SAGEII） ozone profiles and University of Wyoming （UWYO） water vapor profiles were applied to validate the applicability of PTR model. RMSre was 0.437~ for ozone transmittance. RMSre values were 8.89~ and 2.43% for water vapor transmittance ranges of 1-1~10-is and 1-1~ 10-6, respectively. Furthermore, the optical depth profiles calculated using the PTR model were compared to the results of MODTRAN. Absolute RMS errors （RMSab） for ozone optical depths were within 0.0055 and 0.0523 for water vapor at all of the tested altitudes. Finally, the comparison between the solar heating rate calculated from the transmittance of PTR and Line-by-Line radiative transfer model （LBLRTM） was performed, showing a maximum deviation of 0.238 K d-1 （6% of the corresponding solar heating rate calculated using LBLRTM）. In the troposphere all of the deviations were within 0.08 K d-1. The computational speed of PTR model is nearly two orders of magnitude faster than that of MODTRAN.
