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Relationship between the Water Body Chlorophylla and Water Quality Factors of Wetlands Baiguishan Reservoir 被引量:1
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作者 SHE Qiu-sheng TIAN Xun WANG Guo-zhen JI Xiao-cun LI Jiu-xuan ZHAO Zhen 《Agricultural Science & Technology》 CAS 2011年第4期581-583,591,共4页
[Objective] The aim was to explore the relationship between water body Chlorophyll-a and water quality factors of wetlands Baiguishan reservoir.[Method] Chlorophyll-a and water quality factors of water quality of Wetl... [Objective] The aim was to explore the relationship between water body Chlorophyll-a and water quality factors of wetlands Baiguishan reservoir.[Method] Chlorophyll-a and water quality factors of water quality of Wetlands BaiGuishan Reservoir was studied,the analysis of the relationship on water quality of Wetlands Baiguishan Reservoir was made by use of trophic status indices and SPSS17.0 statistical analysis.[Result] Total phosphorus was an important factor of influence Chlorophyll-a in reservoir,water body had slight eutrophication phenomenon in reservoir of July to October in 2010.[Conclusion] Comprehensive management should be strengthened so as to improve the water quality of Baiguishan wetland. 展开更多
关键词 Wetlands Baiguishan Reservoir CHLOROPHYLL-A Water quality factors RELATIONSHIP
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Comparison of Mode Quality Factors for Equilateral Triangular, Square and Rhombus Optical Micro-Resonators
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作者 黄永箴 国伟华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第2期117-120,共4页
The mode frequencies and the quality factors for the equilateral triangular resonator (ETR), the square resonator (SR) and the rhombus resonator (RR) are numerically calculated by the finite difference time domai... The mode frequencies and the quality factors for the equilateral triangular resonator (ETR), the square resonator (SR) and the rhombus resonator (RR) are numerically calculated by the finite difference time domain technique and the Padé approximation. The numerical results show that the resonant modes confined in an equilateral triangular cavity have much higher quality factors than those in the square or the rhombus cavities. The modes in the ETR are totally confined in transverse direction while those in the SR and RR are only partly confined. For the ETR with the side length of 4μm and the refractive index of 3 2, the mode quality factor of about 5 5×10 3 at the wavelength of 1 55μm has been obtained. 展开更多
关键词 MICRORESONATOR quality factor resonant frequency finite difference time domain technique semiconductor laser
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Estimation of quality factors by energy ratio method 被引量:1
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作者 王宗俊 曹思远 +5 位作者 张浩然 曲英铭 袁殿 杨金浩 张德龙 邵冠铭 《Applied Geophysics》 SCIE CSCD 2015年第1期86-92,122,123,共9页
The quality factor Q, which reflects the energy attenuation of seismic waves in subsurface media, is a diagnostic tool for hydrocarbon detection and reservoir characterization. In this paper, we propose a new Q extrac... The quality factor Q, which reflects the energy attenuation of seismic waves in subsurface media, is a diagnostic tool for hydrocarbon detection and reservoir characterization. In this paper, we propose a new Q extraction method based on the energy ratio before and after the wavelet attenuation, named the energy-ratio method(ERM). The proposed method uses multipoint signal data in the time domain to estimate the wavelet energy without invoking the source wavelet spectrum, which is necessary in conventional Q extraction methods, and is applicable to any source wavelet spectrum; however, it requires high-precision seismic data. Forward zero-offset VSP modeling suggests that the ERM can be used for reliable Q inversion after nonintrinsic attenuation(geometric dispersion, refl ection, and transmission loss) compensation. The application to real zero-offset VSP data shows that the Q values extracted by the ERM and spectral ratio methods are identical, which proves the reliability of the new method. 展开更多
关键词 quality factor Q energy ratio time domain seismic wavelet spectral ratio method
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Bulk GaN-based SAW resonators with high quality factors for wireless temperature sensor
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作者 Hongrui Lv Xianglong Shi +6 位作者 Yujie Ai Zhe Liu Defeng Lin Lifang Jia Zhe Cheng Jie Yang Yun Zhang 《Journal of Semiconductors》 EI CAS CSCD 2022年第11期78-83,共6页
Surface acoustic wave(SAW)resonator with outstanding quality factors of 4829/6775 at the resonant/anti-resonant frequencies has been demonstrated on C-doped semi-insulating bulk GaN.The impact of device parameters inc... Surface acoustic wave(SAW)resonator with outstanding quality factors of 4829/6775 at the resonant/anti-resonant frequencies has been demonstrated on C-doped semi-insulating bulk GaN.The impact of device parameters including aspect ratio of length to width of resonators,number of interdigital transducers,and acoustic propagation direction on resonator performance have been studied.For the first time,we demonstrate wireless temperature sensing from 21.6 to 120℃ with a stable temperature coefficient of frequency of–24.3 ppm/℃ on bulk GaN-based SAW resonators. 展开更多
关键词 surface acoustic wave RESONATOR gallium nitride quality factor temperature sensor
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Effects of air damping on quality factors of different probes in tapping mode atomic force microscopy
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作者 Yu Zeng Guo-Lin Liu +1 位作者 Jin-Hao Liu Zheng Wei 《Chinese Physics B》 SCIE EI CAS 2024年第9期506-519,共14页
The AFM probe in tapping mode is a continuous process of energy dissipation,from moving away from to intermittent contact with the sample surfaces.At present,studies regarding the energy dissipation mechanism of this ... The AFM probe in tapping mode is a continuous process of energy dissipation,from moving away from to intermittent contact with the sample surfaces.At present,studies regarding the energy dissipation mechanism of this continuous process have only been reported sporadically,and there are no systematic explanations or experimental verifications of the energy dissipation mechanism in each stage of the continuous process.The quality factors can be used to characterize the energy dissipation in TM-AFM systems.In this study,the vibration model of the microcantilever beam was established,coupling the vibration and damping effects of the microcantilever beam.The quality factor of the vibrating microcantilever beam under damping was derived,and the air viscous damping when the probe is away from the sample and the air squeeze film damping when the probe is close to the sample were calculated.In addition,the mechanism of the damping effects of different shapes of probes at different tip–sample distances was analyzed.The accuracy of the theoretical simplified model was verified using both experimental and simulation methods.A clearer understanding of the kinetic characteristics and damping mechanism of the TM-AFM was achieved by examining the air damping dissipation mechanism of AFM probes in the tapping mode,which was very important for improving both the quality factor and the imaging quality of the TM-AFM system.This study’s research findings also provided theoretical references and experimental methods for the future study of the energy dissipation mechanism of micro-nano-electromechanical systems. 展开更多
关键词 TM-AFM quality factors air viscous damping air squeeze film damping
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Changing trends and influencing factors of the quality of life of chemotherapy patients with breast cancer 被引量:1
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作者 Zhong-Ping Ai Xiao-Lan Gao +2 位作者 Jin-Feng Li Jian-Rong Zhou You-Feng Wu 《Chinese Nursing Research》 CAS 2017年第1期18-23,共6页
Objective: To understand the changing trajectory of quality of life(QOL) during the treatment courses of breast cancer patients during chemotherapy and to investigate the factors in each treatment course that affec... Objective: To understand the changing trajectory of quality of life(QOL) during the treatment courses of breast cancer patients during chemotherapy and to investigate the factors in each treatment course that affect QOL.Methods: The M.D. Anderson Symptom Inventory Scale, the Hospital Anxiety and Depression Scale(HADS), and the Functional Assessment of Cancer Therapy-Breast(FACT-B) scale were used to perform a survey on 174 breast cancer patients who received the TAC(docetaxel, Adriamycin, and cyclophosphamide) chemotherapy regimen before postoperative chemotherapy and 5-7 days after each chemotherapy course.Results: The QOL scores of the breast cancer patients were the lowest before the postoperative chemotherapy(81.2 ± 19.6) and the highest after the second chemotherapy course(94.5 ± 14.4). After the fourth and fifth chemotherapy courses, the scores were much lower again, with values of 82.7 ± 13.9and 82.6 ± 13.1, respectively. The scores improved again after the sixth chemotherapy course(93.9 ± 18.7). Furthermore, each treatment course had different related symptoms that affected the QOL of the patients.Conclusions: More attention should be paid to the changing trajectory of QOL of patients in all treatment courses and to the influence of treatment-related symptoms on the QOL of patients; moreover, interventions should be adopted by medical care personnel to increase QOL in cancer patients. 展开更多
关键词 Breast cancer Chemotherapy quality of life Changing trajectory Influencing factor
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Measurement of the cavity-loaded quality factor in superconducting radio-frequency systems with mismatched source impedance
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作者 Jin-Ying Ma Cheng-Ye Xu +12 位作者 An-Dong Wu Guo-Dong Jiang Yue Tao Zong-Heng Xue Long-Bo Shi Tian-Cai Jiang Zheng-Long Zhu Zi-Qin Yang Zheng Gao Lie-Peng Sun Gui-Rong Huang Feng Qiu Yuan He 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第8期12-23,共12页
The accurate measurement of parameters such as the cavity-loaded quality factor(Q_(L))and half bandwidth(f_(0.5))is essential for monitoring the performance of superconducting radio-frequency cavities.However,the conv... The accurate measurement of parameters such as the cavity-loaded quality factor(Q_(L))and half bandwidth(f_(0.5))is essential for monitoring the performance of superconducting radio-frequency cavities.However,the conventional"field decay method"employed to calibrate these values requires the cavity to satisfy a"zero-input"condition.This can be challenging when the source impedance is mismatched and produce nonzero forward signals(V_(f))that significantly affect the measurement accuracy.To address this limitation,we developed a modified version of the"field decay method"based on the cavity differential equation.The proposed approach enables the precise calibration of f_(0.5) even under mismatch conditions.We tested the proposed approach on the SRF cavities of the Chinese Accelerator-Driven System Front-End Demo Superconducting Linac and compared the results with those obtained from a network analyzer.The two sets of results were consistent,indicating the usefulness of the proposed approach. 展开更多
关键词 Loaded quality factor Field decay method Superconducting cavity MISMATCH Calibration Cavity differential equation Measurement Accelerator-driven system
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A WSN Node Fault Diagnosis Model Based on BRB with Self-Adaptive Quality Factor
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作者 Guo-Wen Sun Gang Xiang +3 位作者 Wei He Kai Tang Zi-Yi Wang Hai-Long Zhu 《Computers, Materials & Continua》 SCIE EI 2023年第4期1157-1177,共21页
Wireless sensor networks (WSNs) operate in complex and harshenvironments;thus, node faults are inevitable. Therefore, fault diagnosis ofthe WSNs node is essential. Affected by the harsh working environment ofWSNs and ... Wireless sensor networks (WSNs) operate in complex and harshenvironments;thus, node faults are inevitable. Therefore, fault diagnosis ofthe WSNs node is essential. Affected by the harsh working environment ofWSNs and wireless data transmission, the data collected by WSNs containnoisy data, leading to unreliable data among the data features extracted duringfault diagnosis. To reduce the influence of unreliable data features on faultdiagnosis accuracy, this paper proposes a belief rule base (BRB) with a selfadaptivequality factor (BRB-SAQF) fault diagnosis model. First, the datafeatures required for WSN node fault diagnosis are extracted. Second, thequality factors of input attributes are introduced and calculated. Third, themodel inference process with an attribute quality factor is designed. Fourth,the projection covariance matrix adaptation evolution strategy (P-CMA-ES)algorithm is used to optimize the model’s initial parameters. Finally, the effectivenessof the proposed model is verified by comparing the commonly usedfault diagnosis methods for WSN nodes with the BRB method consideringstatic attribute reliability (BRB-Sr). The experimental results show that BRBSAQFcan reduce the influence of unreliable data features. The self-adaptivequality factor calculation method is more reasonable and accurate than thestatic attribute reliability method. 展开更多
关键词 Self-adaptive quality factor belief rule base wireless sensor networks fault diagnosis
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Impact factors and improvement measures of enviroment quality in cleaning operating room
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作者 陈小娣 《外科研究与新技术》 2011年第4期266-266,共1页
Objective To analyze the factors that impact the environment quality of cleaning operating room and to discuss improvement measurement. Methods Environment bacteria testing results and prevalence of surgical incision ... Objective To analyze the factors that impact the environment quality of cleaning operating room and to discuss improvement measurement. Methods Environment bacteria testing results and prevalence of surgical incision infection in cleaning operating room were retro- 展开更多
关键词 Impact factors and improvement measures of enviroment quality in cleaning operating room
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Investigation on photonic crystal nanobeam cavity based on mixed diamond–circular holes
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作者 Jingtong Bin Kerui Feng +4 位作者 Shang Ma Ke Liu Yong Cheng Jing Chen Qifa Liu 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期63-70,共8页
A photonic crystal nanobeam cavity(M-PCNC)with a structure incorporating a mixture of diamond-shaped and circular air holes is pro-posed.The performance of the cavity is simulated and studied theoretically.Using thefin... A photonic crystal nanobeam cavity(M-PCNC)with a structure incorporating a mixture of diamond-shaped and circular air holes is pro-posed.The performance of the cavity is simulated and studied theoretically.Using thefinite-difference time-domain method,the parameters of the M-PCNC,including cavity thickness and width,lattice constant,and radii and numbers of holes,are optimized,with the quality factor Q and mode volume Vm as performance indicators.Mutual modulation of the lattice constant and hole radius enable the proposed M-PCNC to realize outstanding performance.The optimized cavity possesses a high quality factor Q 1.45105 and an ultra-small mode=×volume Vm 0.01(λ/n)[Zeng et al.,Opt Lett 2023:48;3981–3984]in the telecommunications wavelength range.Light can be progres-=sively squeezed in both the propagation direction and the perpendicular in-plane direction by a series of interlocked anti-slots and slots in the diamond-shaped hole structure.Thereby,the energy can be confined within a small mode volume to achieve an ultra-high Q/Vm ratio. 展开更多
关键词 Photonic crystal nanobeam cavity Mixed diamond–circular holes Slots and anti-slots FDTD simulation quality factor Mode volume
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A mechanically coupled MEMS filter with high-Q width extensional mode resonators
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作者 Wei Wang Wenli Liu +5 位作者 Junyuan Zhao Bo Niu Zeyu Wu Yinfang Zhu Jinling Yang Fuhua Yang 《Journal of Semiconductors》 EI CAS CSCD 2024年第8期41-48,共8页
This work presents a novel radio frequency(RF)narrowband Si micro-electro-mechanical systems(MEMS)filter based on capacitively transduced slotted width extensional mode(WEM)resonators.The flexibility of the plate lead... This work presents a novel radio frequency(RF)narrowband Si micro-electro-mechanical systems(MEMS)filter based on capacitively transduced slotted width extensional mode(WEM)resonators.The flexibility of the plate leads to multiple modes near the target frequency.The high Q-factor resonators of around 100000 enable narrow bandwidth filters with small size and simplified design.The 1-wavelength and 2-wavelength WEMs were first developed as a pair of coupled modes to form a passband.To reduce bandwidth,two plates are coupled with aλ-length coupling beam.The 79.69 MHz coupled plate filter(CPF)achieved a narrow bandwidth of 8.8 kHz,corresponding to a tiny 0.011%.The CPF exhibits an impressive 34.84 dB stopband rejection and 7.82 dB insertion loss with near-zero passband ripple.In summary,the RF MEMS filter presented in this work shows promising potential for application in RF transceiver front-ends. 展开更多
关键词 MEMS narrowband filter mechanically coupling quality factor width extensional mode
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Effects of Water Quality on the Distribution of Chinese Giant Salamander(Andrias davidianus)in Guizhou Province,China 被引量:1
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作者 Xue LI Jingcai LV +2 位作者 Shize LI Ning XU Gang WEI 《Agricultural Science & Technology》 CAS 2017年第8期1500-1504,共5页
13 water quality parameters were tested from 38 reaches of 34 counties in Guizhou where Chinese giant salamander(Andrias davidianus) distributed over the past 30 years. Dissolved oxygen and p H were found to be signif... 13 water quality parameters were tested from 38 reaches of 34 counties in Guizhou where Chinese giant salamander(Andrias davidianus) distributed over the past 30 years. Dissolved oxygen and p H were found to be significant determinants of the species distribution in recent years(P<0.05). There was no Chinese giant salamander distribution in the recent five years in rivers with dissolved solids of greater than 415 mg/L, conductivity of greater than 639 us/cm, salinity of greater than 0.31 ppt and total hardness of greater than 150 mg/L. Sensitive to environment, the Chinese giant salamander is an important indicator for environmental quality, so it could be used as one of the environmental indicator. Eutrophication, chemical fertilizer, pesticides and inorganic pollutants may be one of reasons driving wild CGS into extinction. 展开更多
关键词 Chinese giant salamander (Andrias davidianus) Guizhou province Water quality factors
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Comparative Analysis on the Quality Components in Vicia faba L. of Different Genotypes
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作者 葛红 缪亚梅 +3 位作者 王学军 汪凯华 陈满峰 卢玉彬 《Agricultural Science & Technology》 CAS 2016年第2期338-340,343,共4页
With 12 Vicia faba L. varieties of different genotypes as the research ma- terials, the contents of 9 kinds of quality factors of protein, fat, free amino acid as well as beneficial mineral elements were analyzed with... With 12 Vicia faba L. varieties of different genotypes as the research ma- terials, the contents of 9 kinds of quality factors of protein, fat, free amino acid as well as beneficial mineral elements were analyzed with the aim to provide the nec- essary theoretical basis for the selection of new varieties of high quality faba beans. The results showed that in the faba beans of different genotypes, the protein content ranged from 27.9% to 31.2%, fat content of 1.2-1.4%, tannin content of 4 700-5 280 mg/kg, iron content of 47.45-67.15 mgJkg, calcium content of 571.30-1 397.22 mg/kg, zinc content of 47.34-66.10 mg/kg, potassium content of 1.09-1.38%, and selenium content ranged from 0.031 mg/kg to 0.064 mg/kg. There were significant differences in the contents of different free amino acids between different genotypes, and the total free amino acid content was between 1.062% and 0.915%. 展开更多
关键词 Vicia faba L. GENOTYPE quality factor
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Novel S-slot DGS with high quality factor
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作者 朱轶智 张晓娟 方广有 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期431-434,共4页
In order to solve the problem that the quality factor ( Q factor) of the conventional defected ground structure (DGS)is not high and cannot produce a sharp resonant band, a novel S-slot DGS is presented. Compared ... In order to solve the problem that the quality factor ( Q factor) of the conventional defected ground structure (DGS)is not high and cannot produce a sharp resonant band, a novel S-slot DGS is presented. Compared with the conventional DGS, the proposed S-slot DGS has a much higher Q factor, a quite simpler layout and a steeper band rejection. Its equivalent circuit model is extracted by analyzing the transfer characteristics, and design parameters are calculated according to the deducted equations. Characteristics of this type of DGS are investigated with variable dimension parameters and an experiential method for the design of the S-slot DGS is summarized. Finally, a sample of a compact S-slot DGS unit resonated at 4. 64 GHz is fabricated. Its Q factor is as high as 39. 66 and its size is only 5.00 mm × 1.40 mm, with a steep resonant band and a low insertion-loss passband. The measured results show a good agreement with simulation, which demonstrates the applicability of the S-slot DGS in practical engineering. 展开更多
关键词 S-slot defected ground structure (DGS) quality factor
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Modeling and Analysis of Mechanical Quality Factor of the Resonator for Cylinder Vibratory Gyroscope 被引量:5
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作者 XI Xiang WU Xuezhong +1 位作者 WU Yulie ZHANG Yongmeng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第1期180-189,共10页
Mechanical Quality factor(Q factor) of the resonator is an important parameter for the cylinder vibratory gyroscope(CVG). Traditional analytical methods mainly focus on a partial energy loss during the vibration p... Mechanical Quality factor(Q factor) of the resonator is an important parameter for the cylinder vibratory gyroscope(CVG). Traditional analytical methods mainly focus on a partial energy loss during the vibration process of the CVG resonator, thus are not accurate for the mechanical Q factor prediction. Therefore an integrated model including air damping loss, surface defect loss, support loss, thermoelastic damping loss and internal friction loss is proposed to obtain the mechanical Q factor of the CVG resonator. Based on structural dynamics and energy dissipation analysis, the contribution of each energy loss to the total mechanical Q factor is quantificationally analyzed. For the resonator with radius ranging from 10 mm to 20 mm, its mechanical Q factor is mainly related to the support loss, thermoelastic damping loss and internal friction loss, which are fundamentally determined by the geometric sizes and material properties of the resonator. In addition, resonators made of alloy 3J53 (Ni42CrTiA1), with different sizes, were experimentally fabricated to test the mechanical Q factor. The theoretical model is well verified by the experimental data, thus provides an effective theoretical method to design and predict the mechanical Q factor of the CVG resonator. 展开更多
关键词 mechanical quality factor cylinder vibratory gyroscope energy loss
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Ultrahigh accelerating gradient and quality factor of CEPC 650 MHz superconducting radio-frequency cavity 被引量:3
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作者 Peng Sha Wei-Min Pan +9 位作者 Song Jin Ji-Yuan Zhai Zheng-Hui Mi Bai-Qi Liu Chao Dong Fei-Si He Rui Ge Liang-Rui Sun Shi-Ao Zheng Ling-Xi Ye 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第10期33-40,共8页
Two 650 MHz single-cell superconducting radio-frequency(SRF)cavities used for the Circular Electron Positron Collider(CEPC)were studied to achieve a high accelerating gradient(E_(acc))and high intrinsic quality factor... Two 650 MHz single-cell superconducting radio-frequency(SRF)cavities used for the Circular Electron Positron Collider(CEPC)were studied to achieve a high accelerating gradient(E_(acc))and high intrinsic quality factor(Q_(0)).The 650 MHz single-cell cavities were subjected to a combination of buffered chemical polishing(BCP)and electropolishing(EP),and their E_(acc) exceeded40 MV/m.Such a high E_(acc) may result from the cold EP with more uniform removal.BCP is easy,cheap,and rough,whereas EP is complicated,expensive,and precise Therefore,the combination of BCP and EP investigated in this study is suitable for surface treatments of mass SRF cavities.Medium temperature(mid-T)furnace baking was also conducted,which demonstrated an ultrahigh Q_(0) of 8×10^(10) at 22 MV/m for both cavities,and an extremely low BCS resistance(R_(BCS))of~1.0 nΩwas achieved a2.0 K. 展开更多
关键词 SRF cavity Accelerating gradient quality factor ELECTROPOLISHING Vertical test
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Joint inversion method for interval quality factor based on amplitude and phase information 被引量:1
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作者 Cao Dan-Ping Li Yue +1 位作者 Sun Wen-Guo Liang Kai 《Applied Geophysics》 SCIE CSCD 2019年第2期199-208,253-254,共12页
Estimating the quality factor Q accurately signifi cantly improves the seismic data resolution and reservoir characterization.The commonly used log-spectral ratio method uses least-squares fi tting to obtain Q values ... Estimating the quality factor Q accurately signifi cantly improves the seismic data resolution and reservoir characterization.The commonly used log-spectral ratio method uses least-squares fi tting to obtain Q values and involves only the amplitude information of seismic data while neglecting phase information.This paper proposes a joint interval Q inversion method based on the spectral ratio method and employs both amplitude and phase information to improve the accuracy.Based on the assumption that Q is independent of frequency,the nonlinear relation between the Q value and the two types of information is jointly used to construct an objective function,which clarifies the quantitative relation between amplitude spectrum,phase information,and Q value.The interval Q value can be inverted by calculating the minimum value of the objective function.The model test exhibits that the proposed method has higher precision and stability than the spectral ratio method;furthermore,the application to field data demonstrates that accurate Q inversion results are consistent with reservoir characteristics. 展开更多
关键词 viscoelastic medium quality factor AMPLITUDE PHASE
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Effect of the desolventizing/toasting process on chemical composition and protein quality of rapeseed meal 被引量:2
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作者 Rainer Mosenthin Ulrike Messerschmidt +3 位作者 Nadja Sauer Patrick Carre Alain Quinsac Friedrich Schone 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第1期205-216,共12页
Background: During processing in a desolventizer/toaster(DT), rapeseed meal(RSM) is heated to evaporate the hexane and to reduce the level of heat-labile anti-nutritional factors such as glucosinolates(GSL). Ho... Background: During processing in a desolventizer/toaster(DT), rapeseed meal(RSM) is heated to evaporate the hexane and to reduce the level of heat-labile anti-nutritional factors such as glucosinolates(GSL). However, excessive heat treatment may reduce amino acid(AA) content in addition to lower AA digestibility and availability in RSM. The objective of the present study was to produce from one batch of a 00-rapeseed variety(17 μmol GSL/g dry matter(DM), seed grade quality) five differently processed RSM under standardized and defined conditions in a pilot plant,and to determine the impact of these different treatments on protein solubility and chemical composition, in particular with regard to contents of AA including reactive Lys(rL ys) and levels of total and individual GSL.Methods: Four RSM were exposed to wet toasting conditions(WetT C) with increasing residence time in the DT of 48,64, 76, and 93 min. A blend of these four RSM was further processed, starting with saturated steam processing(〈 100 °C)and followed by exposure to dry toasting conditions(DryT C) to further reduce the GSL content in this RSM.Results: The contents of neutral detergent fiber and neutral detergent fiber bound crude protein(CP) increased linearly(P 〈 0.05), as residence time of RSM in the DT increased from 48 to 93 min, whereas contents of total and most individual GSL and those of Lys, rL ys, Cys, and the calculated ratio of Lys:CP and r Lys:CP decreased linearly(P ≤ 0.05).The combination of wet heating and DryT C resulted in the lowest GSL content compared to RSM produced under WetT C, but was associated with lowest protein solubility.Conclusions: It can be concluded that by increasing residence time in the DT or using alternative processing conditions such as wet heating combined with DryT C, contents of total and individual GSL in RSM can be substantially reduced.Further in vivo studies are warranted to elucidate if and to which extent the observed differences in protein quality and GSL content between RSM may affect digestibility and bioavailability of AA in monogastric animals. 展开更多
关键词 Anti-nutritional factor Glucosinolate Processing Protein quality Rapeseed meal
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Quality of Sleep at the Ward after Cardiothoracic Surgery 被引量:2
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作者 Jozefine Propper Richard van Valen +2 位作者 Ron Tvan Domburg Maaike Brunott Ad J.J.C.Bogers 《Open Journal of Nursing》 2015年第6期529-537,共9页
Objective: Sleeping problems are among the issues most mentioned by patients after cardiothoracic surgery. These problems can have a negative effect on duration of the hospital stay and recovery. In the ward of our ca... Objective: Sleeping problems are among the issues most mentioned by patients after cardiothoracic surgery. These problems can have a negative effect on duration of the hospital stay and recovery. In the ward of our cardiothoracic surgery department, a study was initiated to assess the quality of sleep after cardiothoracic surgery. The primary objective was to investigate the effect of cardiothoracic surgery on the quality of sleep. The secondary objective was to investigate the quality of sleep. Correlations with perioperative factors and related issues such as the type of surgery and medication were sought. Methods: A consecutive prospective cohort study was initiated (N = 72). The study used validated questionnaires to assess sleep: the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS), the Verran Snyder-Halpern Sleep Scale (VSH) and the Factors Influencing Sleep Quality (FISQ). Results: The PSQI showed that the quality of sleep one month after surgery was inferior to the quality of sleep before surgery (p-value: 0.03). The efficiency of sleep (time spent in bed) was higher after surgery then before surgery (p-value: 0.01). The VSH showed increased impaired sleep on the third night after surgery. The most disruptive factors were not being comfortable in a hospital bed, pain and the noise of medical devices. Conclusions: The quality of sleep after cardiothoracic surgery is worse when compared with the preoperative situation. The chief influencing factors are discomfort in bed, pain and disturbance from medical devices. The use of pain medication does not improve the quality of sleep. 展开更多
关键词 Cardiac Surgery Thoracic Surgery SLEEP Sleep Deprivation factors Influencing Sleep quality (FISQ)
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A high-quality-factor ultra-narrowband perfect metamaterial absorber based on monolayer molybdenum disulfide
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作者 Liying Jiang Yingting Yi +7 位作者 Yijun Tang Zhiyou Li Zao Yi Li Liu Xifang Chen Ronghua Jian Pinghui Wu Peiguang Yan 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第3期571-574,共4页
In order to significantly improve the absorption efficiency of monolayer molybdenum disulfide(M-MoS_(2)), an ultranarrowband M-MoS_(2)metamaterial absorber was obtained through theoretical analysis and numerical calcu... In order to significantly improve the absorption efficiency of monolayer molybdenum disulfide(M-MoS_(2)), an ultranarrowband M-MoS_(2)metamaterial absorber was obtained through theoretical analysis and numerical calculation using the finite difference time domain method. The physical mechanism can be better analyzed through critical coupling and guided mode resonance. Its absorption rate at λ = 806.41 nm is as high as 99.8%, which is more than 12 times that of bare MMoS_(2). From the simulation results, adjusting the geometric parameters of the structure can control the resonant wavelength range of the M-MoS_(2). In addition, we also found that the maximum quality factor is 1256.8. The numerical result shows that the design provides new possibilities for ultra-narrowband M-MoS_(2) perfect absorbers in the near-infrared spectrum.The results of this work indicate that the designed structure has excellent prospects for application in wavelength-selective photoluminescence and photodetection. 展开更多
关键词 metamaterials ultra-narrowband high quality factor critical coupling
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