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Design of weak current measurement system and research on temperature impact

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Nuclear Science and Techniques 2024年第4期35卷 46-56页

作者： Chu-Xiang Zhao San-Gang Li Rong-Rong Su Li yang Ming-Zhe Liu qing-Yue Xue shan Liao Zhi Zhou qing-shan Tan Xian-Guo Tuo Yi Cheng College of Nuclear Technology and Automation Engineering Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China University of Science and Technology of China Hefei 230026China School of Physics and Electronic Engineering Sichuan University of Science and EngineeringZigong 643000China

A dedicated weak current measurement system was designed to measure the weak currents generated by the neutron ionization *** system incorporates a second-order low-pass filter circuit and the Kalman filtering algorithm to effectively filter out noise and minimize interference in the measurement *** conducted under normal temperature conditions has demonstrated the system's high precision ***,it was observed that temperature variations can affect the measurement *** were collected across temperatures ranging from -20 to 70℃,and a temperature correction model was established through linear regression fitting to address this *** feasibility of the temperature correction model was confirmed at temperatures of -5 and 40℃,where relative errors remained below 0.1% after applying the temperature *** research indicates that the designed measurement system exhibits excellent temperature adaptability and high precision,making it particularly suitable for measuring weak currents.

关键词： Weak current measurement system Neutron ionization chamber Kalman filter algorithm Temperature correction model

Traditional herbal formula Sini Powder extract produces antidepressantlike effects through stress-related mechanisms in rats

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Chinese Journal of Natural Medicines 2016年第8期14卷 590-598页

作者： WEI shan-shan yang He-Jin Huang Jia-Wen LU Xue-Ping PENG Ling-Fang WANG qing-Guo School of Basic Medicine Beijing University of Chinese Medicine Department of Drug Screening Yunnan Institute of Materia Medica

Sini Powder(SP), a traditional Chinese herbal formula, has long been used to treat depression in patients, although the underlying mechanisms remain to be elucidated. In the present study, we found that rats treated with SP extract for 7 days showed a significant increase in swimming time and reduction in immobility time in forced swimming test in a dose-dependent manner, without changes in locomotion. These effects could be attributed to SP's modulation of the hypothalamus-pituitary-adrenal axis, because a single pretreatment of SP extract could rescue increased serum corticosterone and plasma adrenocorticotropin levels induced by acute elevated platform stress. A single pretreatment of SP extract could also elevate the m RNA expression of hippocampal glucocorticoid receptors. In conclusion, our results suggest that SP extract may act as an anti-stress medication to produce antidepressant-like effects.

关键词： Sini Powder extract Antidepressant-like Hypothalamic-pituitary-adrenal axis Glucocorticoid receptor

Event-based optimization with random packet dropping

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Science China(Information Sciences) 2020年第11期63卷 175-194页

作者： qing-shan JIA Jing-Xian TANG Zhenning LANG Center for Intelligent and Networked Systems Department of AutomationTsinghua University NetEase Inc.

Event-based optimization(EBO) provides a general framework for policy optimization in many discrete event dynamic systems where decision making is triggered by events that represent state transitions with common features. Because the number of events can be defined by the user and usually increases linearly with respect to the system scale, EBO has good potential to address large-scale problems where the state space grows exponentially. However, in many practical systems, sensors are geographically distributed and connected to a central controller through imperfect communication channels. Therefore, events observed by the sensors may not reach the controller. Optimization methods of event-based policies in these cases have not yet been identified. In this paper, we consider this important problem and make three major contributions. First, we formulate a mathematical EBO model in which the communication between sensors and controllers is subject to random packet dropping. Second, we show that this EBO model can be converted to another EBO model with perfect communication. Then, the performance difference equation and the performance derivative equation for event-based policies are straightforward to develop. One gradient-based policy iteration algorithm is developed for problems where the state transition probabilities are explicitly known, while another for problems where they are unknown. Third, the performance of the algorithms and the impact of the packet dropping probability on policy performance are numerically demonstrated on a single-zone occupant level estimation problem in buildings.

关键词： event-based optimization packet dropping discrete event dynamic systems

Synthesis and Crystal Structure of Methyl(7,7-Dimethyl-2-amino-4-(4-chlorophenyl)-5-oxo-5,6,7,8-tetrahydro-4H-benzo-[b]-pyran-3-yl)Carboxylate

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Chinese Journal of Structural Chemistry 2002年第6期21卷 597-600页

作者： WANGXiang－shan SHIDa－qing 等 DepartmentofChemistry XuzhouNormalUniversityXuzhou221009China ToWhomcorrespndenceshouldbeaddressed

The title compound methyl (7,7-dimemyl-2-amino-4-(4-chlorophenyl)-5-oxo-5,6,7,8-tetrahydro-4H-benzo-[b]-pyran-3-yl) carboxylate (C19H20ClNO4, Mr = 361.81) was synthesized and crystallized. The crystal belongs to triclinic, space group P 1 with a = 8.519(2), b = 10.346(2), c = 11.481(3) A, α = 108.16(1), β = 107.78(2), γ= 91.83(2)°, Z = 2, V = 906.5(3) A3, Dc = 1.326 g/cm3, μ(MoKα) = 0.234 mm-1, F(000) = 380, R = 0.0467 and wR = 0.1270 for 3142 observed reflections (I > 2σ(I)). X-ray analysis reveals that the C(7), C(8), C(9), O(1), C(10) and C(11) atoms form a six-membered ring which adopts a boat conformation. In the ring, the distances of C(8)-C(9) and C(10)-C(11) are 1.332(3) and 1.357(3) A, respectively, which indicates that they are C=C double bonds. Another six-membered ring (C(8)-C(9)-C(15)-C(14)-C(13)-C(12)) adopts the half-chair confonnation. In addition, there are intermolecular hydrogen bonds in the crystal structure.

关键词： crystal structure benzo-[b]-pyran synthesis

On distributed event-based optimization for shared economy in cyber-physical energy systems

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Science China(Information Sciences) 2018年第11期61卷 11-13页

作者： qing-shan JIA Junjie WU Center for Intelligent and Networked Systems (CFINS) Department of AutomationBeijing National Research Center for Information Science and Technology (BNRist)Tsinghua University

Dear editor,In order to accommodate the sharp increase in energy consumption and environmental pollution, it is important to coordinate the supply and the demand. This has become a key feature in a cyberphysical energy system (CPES), where the energy consumer and supplier share information with each other to improve the overall energy efficiency and therefore to reduce the environmental *** economy has risen sharply across the globe and becomes an effective model to improve the efficiency in an investment. Examples include but are

关键词： Figure EBO On distributed event-based optimization for shared economy in cyber-physical energy systems

Fabry-Perot interference and piezo-phototronic effect enhanced flexible MoS_(2) photodetector

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Nano Research 2022年第5期15卷 4395-4402页

作者： Xuexia Chen Xun yang qing Lou Yuan Zhang Yancheng Chen Yacong Lu Lin Dong Chong-Xin shan Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Materials PhysicsMinistry of Educationand School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China

Flexible photodetectors(PDs)are indispensable components for next-generation wearable ***,two-dimensional(2D)materials have been implemented as functional flexible optoelectronic devices due to their characteristics of atomically thin layers,excellent flexibility,and strain *** this work,we developed a flexible photodetector based on MoS_(2)/NiO heterojunction,and Fabry-Perot(F-P)and piezo-phototronic effect have been employed to enhance the responsivity(R)and external quantum efficiency(EQE)of the *** F-P effect is utilized to improve the optical absorption of the MoS_(2),resulting in an enhancement in the photoluminescence(PL)of monolayer MoS_(2) and the EQE of the photodetector by 30 and 130 times,*** flexible photodetector exhibits an ultrahigh detectivity(D*)of 2.6×10^(14) Jones,which is the highest value ever reported for flexible MoS_(2) *** piezo-potential of monolayer MoS_(2) decreases the valence band offset at the interface of MoS_(2)/NiO,which increases the transfer efficiency of the photon-generated carriers *** 1.17%tensile strain,the R of the flexible photodetector can be enhanced by 271%.This research may provide a universal strategy for the design and performance optimization of 2D materials heterostructures for flexible optoelectronics.

关键词： flexible photodetector MoS_(2) Fabry-Perot(F-P)interference piezo-phototronic effect

Design and performance study of a dielectric-filled cavity beam current monitor for HUST-PTF

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Nuclear Science and Techniques 2023年第8期34卷 75-85页

作者： Ji-qing Li Kuan-Jun Fan Zheng-Zheng Liu Jian Wang Qu-shan Chen Jin-Feng yang State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China The Institute of Scientific and Industrial Research Osaka University8-1 MihogaokaIbarakiOsaka 567-0047Japan

To guarantee the exact proton dose applied to patients and ensure treatment safety while disrupting and destroying tumor cells,it is essential to accurately monitor the proton beam current in real time during patient *** clinical treatment requires a proton beam current in the∼nA range,nondestructive beam current monitors(BCMs)are preferred to minimize the degradation of beam ***,this poses significant challenges in accurately monitoring such extremely low beam *** study proposes a cavity-type BCM equipped with a dielectric plate to reduce its dimensions and achieve sufficient measurement sensitivity for practical requirements.A prototype cavity BCM was fabricated,and off-line testing was performed using a metal wire to simulate the beam to study its *** the simulation and experi-mental results showed that the cavity BCM could measure ultralow proton beam currents with a resolution up to 0.03 nA.

关键词： Proton therapy Beam current Cavity BCM Nondestructive

Association of Lysosome Associated Protein Transmembrane 4 Beta Gene Polymorphism with the Risk of Pancreatic Cancer

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Chinese Journal of Cancer Research 2010年第4期22卷 291-295页

作者： shan Wang qing-Yun Zhang Key Laboratory of Carcinogenesis and Translational Research（Ministry of Education） Clinical Laboratory Peking University Cancer Hospital ＆ Institute Beijing 100142 China

Objective： Lysosome associated protein transmembrane 4 beta （LAPTM4B） was originally identified as a gene in human hepatocellular carcinoma （HCC）. It was successfully cloned by fluorescence differential display, rapid amplification of cDNA ends （RACE） and reverse transcription polymerase chain reaction （RT-PCR）. Previous study showed that the novel gene played an important role in the occurrence, development, migration and prognosis of tumors. Pancreatic cancer is an aggressive malignancy with the majority of patients dying within one year after diagnosis. This study tries to find out the relationship between lysosome associated protein transmembrane 4 beta gene polymorphism and the susceptibility of pancreatic cancer. Methods： A case-control study was conducted in China, including 58 pancreatic cancer cases and 156 healthy controls. Human genomic DNA was used as the template, polymerase chain reaction （PCR） was used to detect the distribution of LAPTM4B genotype. Analyses Odds ratio （OR） and corresponding 95% confidence interval （95%CI） with logistic regression were performed. Results： Two alleles of LAPTM4B generated three kinds of genotypes in population, ＊1/1, ＊1/2, and ＊2/2. The genotype frequency of ＊1/1, ＊1/2 and ＊2/2 in the pancreatic cancer group were 41.4%, 44.8% and 13.8% respectively, which were not significantly different from those of healthy group （47.4%, 42.9%, 9.6%）（P=0.773, P=0.291）. Also the ＊2 allele frequency of LAPTM4B among pancreatic cancer had no significantly difference with the controls （P=0.354）. When compared to the ＊1 allele, the people with ＊2 allele had no increased risk of pancreatic cancer. Conclusion： The gene polymorphism of LAPTM4B may not influence the susceptibility of pancreatic cancer.

关键词： Polymorphism Lysosome associated protein transmembrane 4 beta Pancreatic cancer Susceptibility

Effect of Lattice Distortion on Charge Order in Manganites at Doping x=0.5

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Communications in Theoretical Physics 2005年第1期43卷 179-186页

作者： WANGHai-Long TIANGuang-shan LINHai-qing SchoolofPhysics PekingUniversityBeijing100871China SchoolofPhysics PekingUniversityBeijing100871China／／DepartmentofPhysicstheChineseUniversityofHongKongShatinN.T.HongKongChina

In the present paper, we continue our investigation on the antiferromagneticorigin of the charge order observed in the halt-doped manganese. By introducing aSu-Schrieffer-Heeger (SSH) type of perturbation interaction to the double-exchange Hamiltonian, wecalculate again its ground-state phase diagram at Glling x = 0.5 by the unrestricted real-spaceHartree-Fock approximation method. We find that, as the SSH electron-phonon interaction increases,the charge order parameter decreases to zero rapidly but the CE-type antiferromagnetic order becomesmore stable. In other words, the charge order is much more fragile than the CE-type or theNeel-type antiferromagnetic orders under the electron-phonon perturbation. These results support theproposed theory in the recent publications that the charge order in these systems is induced by theantiferromagnetic correlations.

关键词： manganites charge ordered phases antiferromagnetic correlation