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President chen Jia' er Visited Russia

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Science Foundation in China 2003年第1期 5-6页

作者： (chen Wentao, chen huai)

Professor chen Jia’er, President of National Natural Science Foundation of China (NSFC) visited Russia during April 20-23, 2003 at the invitation of Russian Foundation for Basic Research (RFBR). During the visit, President chen Jia’er had friendly and productive meetings with leaders of RFBR and the Russian Academy of Sciences. Both sides expressed their satisfaction on the many joint efforts and progress in promoting the

关键词： chen President chen Jia er Visited Russia

Design, fabrication, and testing of low-group-velocity S-band traveling-wave accelerating structure

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Nuclear Science and Techniques 2022年第11期33卷 133-143页

作者： Xian-Cai Lin Hao Zha Jia-Ru Shi Liu-Yuan Zhou Yi-Fan Liang Jian Gao Qiang Gao huai-Bi chen Chuan-Xiang Tang Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

To implement the Tsinghua Thomson Scattering X-ray Source upgrade plan and the Very Compact Inverse Compton Scattering Gamma-ray Source (VIGAS) program, a new 1.5-m traveling-wave accelerating structure was designed to replace the old 3-m SLAC-type structure with the aim of increasing the accelerating gradient from15 to 30 MV/m. The new type of structure works in the 3π/4 mode with a comparatively low group velocity varying from 0.007c to 0.003c to increase the accelerating gradient at a given power. An elliptical iris was employed to reduce the surface field enhancement. The filling process of the low-group-velocity structure was analyzed using a circuit model. After fabrication, the structure was precisely tuned using the non-contact tuning method, followed by detailed low-power radiofrequency measurements. The structure was first installed and utilized at a beamline for the terahertz experiment at Tsinghua University. After 120 h of conditioning, it is now operating at a gradient of 24.2 MV/m and a 20.7-MW input power, with the klystron operating at its full power. It is expected to generate an accelerating gradient of 30 MV/m when the klystron power is upgraded to 30 MW in the near future.

关键词： Traveling-wave accelerating structure Cavity optimization Tuning method High-power test

Fabrication,tuning,and high-gradient testing of an X-band traveling-wave accelerating structure for VIGAS

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Nuclear Science and Techniques 2022年第8期33卷 77-88页

作者： Xian-Cai Lin Hao Zha Jia-Ru Shi Qiang Gao Jia-Yang Liu Liu-Yuan Zhou Jian Gao huai-Bi chen Chuan-Xiang Tang Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

X-band high-gradient linear accelerators are a challenging and attractive technology for compact electron linear-accelerator *** Very Compact Inverse Compton Scattering Gamma-ray Source(VIGAS)program at Tsinghua University will utilize X-band high-gradient accelerating structures to boost the electron beam from 50 to 350 MeV over a short distance.A constant-impedance traveling-wave structure consisting of 72 cells working in the 2π/3 mode was designed and fabricated for this *** tuning and detailed measurements were successfully applied to the *** 180 h of conditioning in the Tsinghua high-power test stand,the structure reached a target gradient of 80 MV/*** breakdown rate versus gradient of this structure was measured and analyzed.

关键词： Traveling-wave accelerating structure X-band high gradient Tuning method High-power test

Research on the Recovery of the Transported Static Image with Channel Errors

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Wuhan University Journal of Natural Sciences 2002年第3期7卷 297-301页

作者： Liu huai\|lin, chen Shu\|zhen  School of Electronic Information, Wuhan University, Wuhan 430072, Hubei,China School of Electronic Information Wuhan University Wuhan Hubei China

A discussion is presented to gain the relationship between the original image and the reconstructed image while errors are mixed with the DCT data of the original image for the transmission. We can find the wrong reconstructed blocks, locate blocks, which are most likely to contain errors and eliminate errors. The method needs no channel error protection, needs no verifiable bits, and needs no extra bandwidth. Experimental results are provided in the end.

关键词： Key words DCT IDCT reconstructed image continuity

Speciation and fractionation of heavy metals in soil experimentally contaminated with Pb, Cd, Cu and Zn together and effects on soil negative surface charge

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Journal of Environmental Sciences 2002年第4期14卷 439-444页

作者： ZHOU Dong mei, HAO Xiu zhen, TU Cong, chen huai man, SI You bin (Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China. )

Speciation and fractionation of heavy metals in soil subsamples experimentally loaded with Pb, Cd, Cu and Zn in orthogonal design was investigated by sequential extraction, and operationally defined as water soluble and exchangeable(SE), weakly specific adsorbed(WSA), Fe and Mn oxides bound(OX) and organic bound(ORG). The results showed that fractions of heavy metals in the soil subsamples depended on their speciation. About 90% of Cd and 75% of Zn existed in soil subsamples in the SE fraction. Lead and Cu existed in soil subsamples as SE, WSA and OX fractions simultaneously, although SE was still the major fraction. Organic bound heavy metals were not clearly apparent in all the soil subsamples. The concentration of some heavy metal fractions in soil subsamples showed the good correlation with ionic impulsion of soil, especially for the SE fraction. Continuous saturation of soil subsamples with 0.20 mol/L NH 4Cl, which is the first step for determination of the negative surface charge of soil by the ion retention method, resulted in desorption of certain heavy metals from the soil. It was found that the percentage desorption of heavy metals from soil subsamples depended greatly on pH, the composition and original heavy metal content of the soil subsamples. However, most of the heavy metals in the soil subsamples were still be retained after multiple saturation. Compared with the parent soil, the negative surface charge of soil subsamples loaded with heavy metals did not show difference significantly from that of the parent one by statistical analysis. Heavy metals existed in the soil subsamples mainly as exchangeable and precipitated simultaneously.

关键词： soil heavy metals speciation soil surface charge

MATHEMATICAL MODEL FOR THE FLOW WITH SUBMERGED AND EMERGED RIGID VEGETATION

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Journal of Hydrodynamics 2009年第5期21卷 722-729页

作者： huai Wen-xin chen Zheng-bing HAN Jie ZHANG Li-xiang ZENG Yu-hong State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan430072 China Department of Engineering Mechanics Kunming University of Science and Technology Kunming 650051 China

The article summarizes previous studies on the flow in open channels with rigid vegetation, and constructs a mathematical model for submerged and emerged rigid vegetation. The model involves the forces balance in the control volume in one-dimensional steady uniform flow. For submerged vegetation, the whole flow is divided into four regions： external region, upper vegetated region, transition region and viscous region. According to the Karrnan similarity theory, the article improves the mixing length expression, and then gives an analytical solution to predict the vertical distribution of stream-wise velocity in the external region. For emerged vegetation, the flow is divided into two region： outer region and viscous region. In the two circumstances, the thicknesses of each region are determined respectively. The comparison between the calculated results and our experimental data and other researchers＇ data proves that the proposed model is effective.

关键词： Karman similarity theory mixing length submerged and emerged rigid vegetation velocity distribution

Malignant fibrous histiocytoma of right atrium

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Chinese Medical Journal 2013年第10期126卷 1994-1995页

作者： chen huai-sheng WANG Wei HONG cheng-ying Intensive Care Unit Second Affiliated Hospital of Jinan UniversityShenzhen People's Hospital Shenzhen Guangdong 518020 China

Afifty-year-old male patient was admitted with dyspnoea and cough. Four days before admission, he wasepisode of dyspnoea, could not prostrate with non- productive cough when he was offered with a gastroscopy examination in a local hospital due to anepithymia. The patient had no history of medication or allergies. However, he had smoked for more than thirty years-sixty cigarettes per day. Chest distress without haemoptysis, pink frothy sputum, apsychia, amaurosis, and fever was developed. The symptoms worsened gradually. On examination at the Department of Emergency, Shenzhen People＇s Hospital, dyspnoea with jugular vein distension and oedema in his head, neck and thoracic region were discovered. The breathing sounds on both lower lungs were low. His heart rate was 100 beats/min without arrhythmia or murmur. His abdomen was soft without rebound tenderness. His liver and spleen were not palpable. Pitting oedema occurred in both low limbs. Furosemide was given, but the symptoms were not relieved.

关键词： cardiac malignant fibrous histiocytoma heart failure metastases

Prostate-derived IL-1βupregulates expression of NMDA receptor in the paraventricular nucleus and shortens ejaculation latency in rats with experimental autoimmune prostatitis

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Asian Journal of Andrology 2022年第2期24卷 213-218页

作者： Jie Yang Jiao-chen Luan Jian-huai chen Qi-Jie Zhang Jian-Xin Xue Ya-Min Wang Guo-Qing Zhu Ning-Hong Song Zeng-Jun Wang Jia-Dong Xia Department of Urology First Affiliated Hospital of Nanjing Medical UniversityNanjing 210008China Department of Andrology Jiangsu Province Hospital of Chinese MedicineAffiliated Hospital of Nanjing University of Chinese MedicineNanjing 210008China Key Laboratory of Cardiovascular Disease and Molecular Intervention Department of PhysiologyNanjing Medical UniversityNanjing 210008China

Experimental autoimmune prostatitis(EAP)-induced persistent inflammatory immune response can significantly upregulate the expression of N-methyl-D-aspartic acid(NMDA)receptors in the paraventricular nucleus(PVN).However,the mechanism has not yet been ***,we screened out the target prostate-derived inflammation cytokines(PDICs)by comparing the inflammatory cytokine levels in peripheral blood and cerebrospinal fluid(CSF)between EAP rats and their *** identifying the target PDIC,qualified males in initial copulatory behavior testing(CBT)were subjected to implanting tubes onto bilateral ***,they were randomly divided into four subgroups(EAP-1,EAP-2,Control-1,and Control-2).After 1-week recovery,EAP-1 rats were microinjected with the target PDIC inhibitor,Control-1 rats were microinjected with the target PDIC,while the EAP-2 and Control-2 subgroups were only treated with the same amount of artificial CSF(aCSF).Results showed that only interleukin-1β(IL-1β)had significantly increased mRNA-expression in the prostate of EAP rats compared to the controls(P<0.001)and significantly higher protein concentrations in both the serum(P=0.001)and CSF(P<0.001)of the EAP groups compared to the Control ***,IL-1βwas identified as the target PDIC which crosses the blood-brain barrier,thereby influencing the central nervous ***,the EAP-1 subgroup displayed a gradually prolonged ejaculation latency(EL)in the last three CBTs(all P<0.01)and a significantly lower expression of NMDA NR1 subunit in the PVN(P=0.043)compared to the respective control groups after a 10-day central administration of IL-1β***,the Control-1 subgroup showed a gradually shortened EL(P<0.01)and a significantly higher NR1 expression(P=0.004)after homochronous IL-1β***,we identified IL-1βas the primary PDIC which shortens EL in EAP ***,further studies should be conducted to elucidate the specific molecular mechanisms throug

关键词： chronic prostatitis N-methyl-D-aspartic acid receptor paraventricular nucleus premature ejaculation prostate-derived inflammation cytokines sympathetic nervous system

Nitrite inhalants use, sexual behaviors and HIV/syphilis infection among men who have sex with men in Chongqing, China

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Infectious Diseases of Poverty 2020年第5期9卷 12-21页

作者： Jin chen Yu-Ling Huang huai-Liang chen Ji Xia Department of Medical Records Management the People's Hospital of Tongliang DistrictChongqingChina Department of STD/HIV Control and Prevention Sichuan provincial Center for Disease Control and PreventionChengduChina Department of Infectious Diseases Prevention and Healthcare the People's Hospital of Chengdu Tianfu New AreaChengduChina

Background:Emerging evidence indicates nitrite inhalants have become increasingly prevalent among men who have sex with men(MSM).The present study aimed to describe the prevalence and correlates of nitrite inhalants use and its association with risky sexual behaviors and human immunodeficiency virus(HIV)/syphilis infection among MSM in Chongqing,a city in China where MSM were burdened with the highest pooled HIV prevalence in the ***:This cross-sectional study was conducted in Chongqing between March 2019 and February *** of demographics,drug use,sexual behaviors and HIV testing was collected through an anonymous *** samples were drawn from each participant for the diagnoses of HIV and *** regression analysis was performed to evaluate factors correlated with nitrite inhalants use and its relationship with risky sexual behaviors and HIV/syphilis ***:Of the 1151 eligible participants,18.9%(218)reported use of at least one type of recreational drugs in the past 6 months,and nitrite inhalants were the most commonly used substance(17.7,95%confidence interval[CI]:15.6-20.2%).The proportions of participants reported engaging in group sex and practicing condomless internal ejaculation during anal sex in the past six months were 5.8%(95%CI:4.4-7.2%)and 41.7%(95%CI:38.7-44.7%),*** general prevalence of HIV and syphilis infection among the enrolled MSM were 16.8%(95%CI:14.7-19.0%)and 12.6%(95%CI:10.7-14.4%),*** positively associated with nitrite inhalants use included:age<25(adjusted odds ratio[aOR]=2.08,95%CI:1.10-3.94),monthly individual income≥CNY 3000(Chinese Yuan)(aOR=1.95,95%CI:1.18-3.22),preferring receptive anal intercourse(aOR=2.27,95%CI:1.34-3.84)and versatile anal intercourse(aOR=2.60,95%CI:1.64-4.13),age at first anal intercourse<18(aOR=1.79,95%CI:1.21-2.67),engaging in group sex in the past six months(aOR=9.34,95%CI:4.95-17.63),having multiple male sex partners in the past

关键词： Nitrite inhalants use Sexual behavior HIV infection Syphilis infection Men who have sex with men