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Fabrication and cold test of prototype of spatially periodic radio frequency quadrupole focusing linac

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Nuclear Science and Techniques 2021年第1期32卷 66-74页

作者： Pei-Yan Yu Bin Zhang feng-feng wang Chen-Xing Li Guo-Zhen Sun Zhi-Jun wang Lu-Bei Liu Chen-Zhang Yuan Yuan He Hu-Shan Xu Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

A 325 MHz aluminum prototype of a spatially periodic RF quadrupole focusing linac was developed at the Institute of Modern Physics,Chinese Academy of Sciences,as a promising candidate for the front end of a high-current *** consists of an alternating series of crossbar H-type drift tubes and RF quadrupole *** to its special geometry,cavity fabrication is a major hurdle for its engineering development and *** this paper,we report the detailed mechanical design of this structure and describe its fabrication process,including machining,assembly,and *** field distribution was measured by the bead-pull *** results show that the field errors of both the accelerating and focusing fields are within an acceptable range.A tuning scheme for this new structure is proposed and *** cold test process and results are presented in *** development of this prototype provides valuable guidance for the application of the spatially periodic RF quadrupole structure.

关键词： Spatially periodic RF quadrupole focusing linac Mechanical structure design Bead-pull measurement

Alignment of beam position monitors in cryomodule of CADS injector Ⅱ

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Nuclear Science and Techniques 2017年第6期28卷 95-100页

作者： Jian-Dong Yuan Yuan He Bin Zhang Jun-Hui Zhang Jun-Xia Wu Yong Zhang feng-feng wang Jun-Jie Yao Guo-Zhen Sun Yu-Qin Wan Institute of Modern Physics Chinese Academy of Sciences

Significant temperature difference(300-77 K or even 4 K) can cause large deformations and displacements of the beam position monitors(BPMs),which affect BPMs measurement resolution or even cause their malfunction in cryogenic *** this paper,to check the offset from the mechanical to electrical center in low temperature(77 K),Fourier's law and finite element method are used to simulate *** tracker and micro-alignment telescope are employed in combined BPM calibration,installation and *** calibration error is<0.02 mm,and the installation and monitoring precision are 0.06 mm and 0.01 mm,*** monitored cryo-deformation agrees well with the simulation *** indicate that the combined alignment can improve performance of the BPM *** these guaranteed the success of running the 9.55 MeV@2.14 mA cw protons.

关键词： Beam position monitors Alignment Fourier’s Law Cryomodule CADS ANSYS

Investigation into the structures and physicochemical properties of multi-component crystals of voriconazole

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Chinese Chemical Letters 2023年第6期34卷 504-511页

作者： Hong-Mei Yu Bao-Xi Zhang Wen-Hui Xing Mei-Ju Liu feng-feng wang Ning-Bo Gong Li Zhang Yang Lu Guan-Hua Du Beijing Key Laboratory of Polymorphic Drugs Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China National Institutes for Food and Drug Control Beijing 102629China Beijing City Key Laboratory of Drug Target Identification and Drug Screening Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Voriconazole(VZL)is a second-generation and broad-spectrum triazole against fungal *** a BCS(biopharmaceutics classification system)class II compound,the poor aqueous solubility has limited its bioavailability and clinical *** to overcome this disadvantage,a cocrystallization strategy based on crystal engineering principles has resulted in five new multi-component crystals of VZL with maleic acid,L-tartaric,protocatechuic,gallic,and 3,5-dinitrobenzoic *** analysis revealed that the hydroxyl/carboxylic acid···triazole N_(3)hydrogen bonding interaction appears as a main supramolecular heterosynthon in the VZL multi-component crystals with organic *** VZL molecule has a flexible conformation in each of the five multi-component *** newly synthesized multi-component crystals showed impressive solubility improvement compared to that of the raw material of *** electrostatic potential surfaces(MEPS)analysis based on density functional(DFT)calculations revealed that hydrogen bond interactions in cocrystals mainly involved pairwise interactions in the global maxima and minima sites,but this rule is not always *** study indicates the potential of cocrystals to improve the solubility and dissolution rate of VZL.

关键词： Multi-component crystal Voriconazole Solubility Dissolution Stability

HIV and intestinal parasite co-infections among a Chinese population: an immunological profile

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Infectious Diseases of Poverty 2013年第1期2卷 144-151,143页

作者： Li-Guang Tian Tian-Ping wang Shan Lv feng-feng wang Jian Guo Xiao-Mei Yin Yu-Chun Cai Mary Kathryn Dickey Peter Steinmann Jia-Xu Chen National Institute of Parasitic Diseases Chinese Center for Disease Control and Prevention(China CDC) WHO Collaborating Centre for Malaria Schistosomiasis and FilariasisKey Laboratory of Parasite and Vector BiologyMinistry of HealthShanghai 200025People’s Republic of China Anhui Institute of Parasitic Disease Control Hefei 241000People’s Republic of China University of Oklahoma Midwest 73110OKUSA Department of Epidemiology and Public Health Swiss Tropical and Public Health Institu

Background:Parasite infections often result in a switch of the human body’s predominant immune reaction from T-helper 1(Th1)-type to ***,parasite infections are widely expected to accelerate the progression of human immunodeficiency virus(HIV)infections to acquired immunodeficiency syndrome(AIDS).In the People’s Republic of China,both parasitic diseases and AIDS are epidemic in certain rural areas,and co-infections are relatively ***,no population-based studies have yet investigated the frequency of HIV and parasite co-infections,and its effects on immune *** studied(1)the immune status of an HIV-infected population,and(2)the effect of co-infection of HIV and intestinal parasites on selected parameters of the human immune ***:A total of 309 HIV-infected individuals were recruited and compared to an age-matched and sex-matched control group of 315 local HIV-negative *** were administered to all participants to obtain information on sociodemographic characteristics,sanitation habits,family income,and recent clinical *** consecutive stool samples and 10 ml samples of venous blood were also collected from each individual for the diagnosis of parasite infections and quantitative measurements of selected cytokines and CD4+T-lymphocytes,***:During the study period,79 HIV-infected individuals were not under highly active antiretroviral therapy(HAART)and were thus included in our analysis;the prevalence of intestinal helminth infections was 6.3%and that of protozoa was 22.8%.The most common protozoan infections were Blastocystis hominis(***)(13.9%)and Cryptosporidium spp.(10.1%).The prevalence of Cryptosporidium *** HIV-infected individuals was significantly higher than that in HIV negative individuals(P0.05).However,the following trend

关键词： HIV Intestinalparasite Co-infection Immunological profile People’s Republic of China

Design study on medium beta superconducting half-wave resonator at IMP

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Nuclear Science and Techniques 2016年第4期27卷 21-27页

作者： An-Dong Wu Sheng-Hu Zhang Wei-Ming Yue Tian-Cai Jiang Yong-Ming Li feng-feng wang Sheng-Xue Zhang Liang-Jian Wen Ran Huang Yuan He Hong-Wei Zhao Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China University of Chinese Academy of Sciences Beijing 100049 China

A 325-MHz superconducting half-wave resonator has been designed with β = 0.51. Three shapes of the inner conductors(race track, ring shape and elliptical shape) were optimized to decrease the peak electromagnetic fields and minimize the dissipated RF power on the cavity walls. In order to suppress the operation frequency shift caused by fluctuations of the helium pressure and maximize the tuning ranges, the frequency shifts and mechanical properties were studied on the electric and magnetic areas. The helium vessel was designed to keep the mechanical structure as robust as possible.

关键词：超导谐振器设计 IMP 射频功率压力波动调谐范围机械性能频率变化

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高亚声速湍流喷流气动噪声数值分析

力学学报 2016年第5期48卷 1049-1060页

作者：冯峰郭力王强中国航天空气动力技术研究院北京100074

为适应航空噪声管制规定要求,发动机喷流噪声控制成为目前气动声学研究中的重要课题,预测分析喷流噪声辐射并揭示其产生机理将为噪声控制奠定基础.采用高精度并行LES(large eddy simulation)方法计算分析马赫数0.9高亚声速喷流的湍流演... 详细信息

为适应航空噪声管制规定要求,发动机喷流噪声控制成为目前气动声学研究中的重要课题,预测分析喷流噪声辐射并揭示其产生机理将为噪声控制奠定基础.采用高精度并行LES(large eddy simulation)方法计算分析马赫数0.9高亚声速喷流的湍流演化和气动噪声现象.首先,仔细验证喷流LES湍流场计算保真性,并分析流场中不同尺度涡结构的演化形态.其次,利用可穿透面FW-H(Ffowcs Williams and Hawkings)方法外推喷流近场声源数据获得精确声辐射远场,进而分析声场主导声模态特性.最后,通过分析声源机制、分离声模态等方法研究势流核末端大尺度拟序涡运动演化形成的低波数波包在噪声主导声模态产生中的重要作用.数值结果表明LES结合可穿透面FW-H方法可精确预测高亚声速喷流的流场及声场特征,且数值分析揭示涡环对并形成的大尺度拟序结构在喷流中心线上沿径向融合,产生了在远场低方位角占优的主导声模态,并构成强指向性声场,噪声峰值方位角约为30?.

关键词：高亚声速喷流声辐射波包 FW-H方法大涡模拟

Effect of Progressive Substitution of Cement and Lime by Powdered Shells Used as a Curing Agent for Dredged Soil in a Port Area

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 88-102页

作者： SUN Yang wang Faxin SU Yaying LI Yiwei HE feng College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Huai'an Research Institute Hohai UniversityHuai'an 223025China Jiangsu Fangyang Industrial Investment Corp.Ltd. Lianyungang 210098China

This study aimed to address the challenges of solid waste utilization,cost reduction,and carbon reduction in the treatment of deep-dredged soil at Xuwei Port in Lianyungang city of *** research in this area was ***,a curing agent made from powdered shells was used to solidify the dredged soil in *** employed laboratory orthogonal tests to investigate the physical and mechanical properties of the powdered shell-based curing *** was collected by conducting experiments to assess the role of powdered shells in the curing process and to determine the optimal ratios of powdered shells to solidified soil for different *** development of strength in solidified soil was studied in both seawater and pure water *** study revealed that the strength of the solidified soil was influenced by the substitution rate of powdered shells and their interaction with *** cement content had a positive effect on *** high-strength solidified soil,the recommended ratio of wet soil:cement:lime:powdered shells were 100:16:4:4,while for low-strength solidified soil,the recommended ratio was 100:5.4:2.4:***,under appropriate conditions,improved short-term strength by promoting the formation of expansive ettringite minerals that contributed to cementation and *** findings suggest that the combination of cement and powdered shells is synergistic,positively affecting the strength of solidified *** recommended ratios provide practical guidance for achieving desired strength levels while considering factors such as cost and carbon *** role of seawater in enhancing short-term strength through crystal formation is noteworthy and can be advantageous for certain *** conclusion,this research demonstrates the potential of using a powdered shell-based curing agent for solidifying dredged soil in an environmentally friendly and cost-effective *** recommended ratios for different str

关键词： carbon reduction and solidification dredged soil abandoned shells orthogonal test chemical additives(lime and cement) unconfined compressive strength(UCS)

Comparison of the closed analytical solution on the parameters of the alignment and surveying of the elements of accelerator under random errors

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Radiation Detection Technology and Methods 2023年第2期7卷 234-247页

作者： Jian-Dong Yuan Jun-Xia Wu feng-feng wang Wen-Jun Chen Guo-Zhen Sun Shao-Ming wang Xu-Dong Zhang Xiao-Dong Zhang Zhi-Jun wang Bin Zhang Yuan He&Jun-Hui Zhang Institute of Modern Physics Chinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Beijing100049China

Purpose Compared with the iterative approximation solution,the analytically rigorous solution of the parameters of the accelerator alignment and surveying is the closed theoretical *** make the calculated error meet the negligible principle,in this paper,such examples of the zero,small angle and small translation,only large translation and no angle,only large angle without translation and large translation and large angle parameters under random errors are *** Furthermore,Singular Value Decomposition,Eigen Value Decomposition,Polar Decomposition,Orthogonal Procrustes Analysis,and Successive Equivalent Differences Transformation are *** In all the above examples,the mutual calculation deviation of Singular Value Decomposition,Eigen Value Decomposition,Polar Decomposition,and Orthogonal Procrustes analysis methods is less than 10 *** calculation accuracy is the highest,and Successive Equivalent Differences Transformation-3 has the largest calculation error,and Successive Equivalent Differences Transformation-N is in the *** results show that the coordinate residuals,parameters offsets and point position errors of the above solutions with random errors are all nearly *** It shows that the closed analytical solution is a rigorous ***,it also shows that the constructed method of the coordinate point pairs is correct.

关键词： Accelerator Alignment Surveying Closed analytical solution

Enhancing Deepfake Detection:Proactive Forensics Techniques Using Digital Watermarking

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Computers, Materials & Continua 2025年第1期82卷 73-102页

作者： Zhimao Lai Saad Arif Cong feng Guangjun Liao Chuntao wang School of Automation Guangdong University and TechnologyGuangzhou510006China School of Immigration Administration(Guangzhou) China People’s Police UniversityGuangzhou510663China Department of Mechanical Engineering College of EngineeringKing Faisal UniversityAl Ahsa31982Saudi Arabia Cyber Police Division Guangzhou Public Security BureauGuangzhou510030China School of Forensic Science and Technology Guangdong Police CollegeGuangzhou510320China College of Mathematics and Informatics South China Agricultural UniversityGuangzhou510642China

With the rapid advancement of visual generative models such as Generative Adversarial Networks(GANs)and stable Diffusion,the creation of highly realistic Deepfake through automated forgery has significantly *** paper examines the advancements inDeepfake detection and defense technologies,emphasizing the shift from passive detection methods to proactive digital watermarking *** detection methods,which involve extracting features from images or videos to identify forgeries,encounter challenges such as poor performance against unknown manipulation techniques and susceptibility to counter-forensic *** contrast,proactive digital watermarking techniques embed specificmarkers into images or videos,facilitating real-time detection and traceability,thereby providing a preemptive defense againstDeepfake *** offer a comprehensive analysis of digitalwatermarking-based forensic techniques,discussing their advantages over passivemethods and highlighting four key benefits:real-time detection,embedded defense,resistance to tampering,and provision of legal ***,the paper identifies gaps in the literature concerning proactive forensic techniques and suggests future research directions,including cross-domain watermarking and adaptive watermarking *** systematically classifying and comparing existing techniques,this review aims to contribute valuable insights for the development of more effective proactive defense strategies in Deepfake forensics.

关键词： Deepfake proactive forensics digital watermarking traceability detection techniques