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Research on Pulsar Time steered Atomic Time Algorithm Based on DPLL

Research in Astronomy and Astrophysics 2024年第3期24卷 237-248页

作者： ze-Hao Zheng Yang Liu Dan shen Fan Feng Jiu-Long Liu Yue-Xin Ma Xiang-Wei Zhu school of Electronic and Communication Engineering Sun Yat-sen UniversityShenzhen 518107China school of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China school of systems science and Engineering Sun Yat-sen UniversityGuangzhou 510275China

In today’s society,there is a wide demand for high-precision and high-stability time service in the fields of electric power,communication,transportation and *** present,the time standard in various countries is mainly based on atomic clocks,but the frequency drift of atomic clocks will affect the long-term stability *** with atomic clocks,millisecond pulsars have better long-term stability and can complement with the excellent short-term stability of atomic *** order to improve the long-term stability of the atomic timescale,and then improve the timing accuracy,this paper proposes an algorithm for steering the atomic clock ensemble(ACE)by ensemble pulsar time(EPT)based on digital phase locked loop(DPLL).First,the ACE and EPT are generated by the ALgOs algorithm,then the ACE is steered by EPT based on DPLL to calibrate the long-term frequency drift of the atomic clock,so that the generated steered atomic time follows both the short-term stability characteristics of ACE and the long-term stability characteristics of EPT,and finally,the steered atomic time is used to calibrate the local cesium *** experimental results show that the long-term stability of atomic time after steering is improved by 2 orders of magnitude compared with that before steering,and the daily drift of a local cesium clock after calibration is less than 9.47 ns in 3 yr,3 orders of magnitude higher than that before calibration on accuracy.

关键词： (stars) pulsars general-time-methods data analysis-instabilities

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Remote sensing of air pollution incorporating integrated-path differential-absorption and coherent-Doppler lidar

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Defence Technology（防务技术） 2024年第1期31卷 594-601页

作者： ze-hou Yang Yong Chen Chun-li Chen Yong-ke Zhang Ji-hui Dong Tao Peng Xiao-feng Li Ding-fu Zhou school of Physics Beijing Institute of TechnologyBeijing 100081China southwest Institute of Technical Physics Chengdu 610041SichuanChina school of Optics and Photonics Beijing Institute of TechnologyBeijing 100081China

An innovative complex lidar system deployed on an airborne rotorcraft platform for remote sensing of atmospheric pollution is proposed and *** system incorporates integrated-path differential absorption lidar(DIAL) and coherent-doppler lidar(CDL) techniques using a dual tunable TEA CO_(2)laser in the 9—11 μm band and a 1.55 μm fiber *** combining the principles of differential absorption detection and pulsed coherent detection,the system enables agile and remote sensing of atmospheric *** static tests validate the system’s real-time detection capabilities,including the measurement of concentration-path-length product(CL),front distance,and path wind speed of air pollution plumes over long distances exceeding 4 *** experiments is conducted with the *** of the pollutant concentration and the wind field is carried out in an approximately 1 km slant range over scanning angle ranges from 45°to 65°,with a radial resolution of 30 m and10 *** test results demonstrate the system’s ability to spatially map atmospheric pollution plumes and predict their motion and dispersion patterns,thereby ensuring the protection of public safety.

关键词： Differential absorption LIDAR Coherent Doppler lidar Remoting sensing Atmospheric pollution

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Keplerate polyoxomolybdate nanoball mediated controllable preparation of metal-doped molybdenum disulfide for electrocatalytic hydrogen evolution in acidic and alkaline media

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Chinese Chemical Letters 2024年第7期35卷 524-528页

作者： Ping Wang Ting Wang Ming Xu ze gao Hongyu Li Bowen Li Yuqi Wang Chaoqun Qu Ming Feng Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education Jilin Normal UniversityChangchun 130103China school of science Changchun University of Science and TechnologyChangchun 130022China

Rationally designed novel cost-effective hydrogen evolution reaction(HER)electrocatalysts with controlled surface composition and advanced structural superiority is extremely critical to optimize the HER ***(POMs)with structural diversity and adjustable element compositions represent a promising precursor for rational design and preparation of HER ***,a series of transition metal-doped Mos_(2)materials with different surface engineered structures(Fe,Cr,V doping and s vacancies)(M-Mos_(2)/CC,M=Fe,Cr and V)were fabricated by a simple hydrothermalvulcanization strategy using Keplerate polyoxomolybdate nanoball({Mo_(72)Fe_(30)},{Mo_(72)Cr_(30)},{Mo_(72)V_(30)},{Mo_(132)})as *** enlarged interlayer spacing as well as the integration of homogeneous transition metal doping and abundant sulfur vacancies endows prepared M-Mos_(2)/CC with superior HER electrocatalytic performance and excellent long-term working stability in both acidic and alkaline *** optimized Fe-Mos_(2)/CC afford current densities of 10 and 50 mA/cm^(2)at overpotentials of 188/272 mV and 194/394 mV in 0.5 mol/L H_(2)sO_(4)and 1.0 mol/L KOH aqueous solution,respectively,outperforming most of reported typical transition metal sulfide-based *** work represents an important breakthrough for POMs-mediated highly efficient transition metal sulfide-based HER electrocatalysts with wide range pH activity and may provide new options for the rational design of promising HER electrocatalysts and beyond.

关键词： Polyoxometalate Electrocatalytic Hydrogen evolution reaction Doping Mos_(2)

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geophysical prediction of organic matter abundance in source rocks based on geochemical analysis:A case study of southwestern Bozhong sag,Bohai sea,China

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Petroleum science 2024年第1期21卷 31-53页

作者： Xiang Wang guang-Di Liu Xiao-Lin Wang Jin-Feng Ma Zhen-Liang Wang Fei-Long Wang ze-Zhang song Chang-Yu Fan state Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of geosciences China University of Petroleum(Beijing)Beijing102249China state Key Laboratory of Continental Dynamics Northwest UniversityXi'an710069ShaanxiChina Department of geology Northwest UniversityXi'an710069ShaanxiChina CNOOC Tianjin Branch Company Tianjin300459China

The Bozhong sag is the largest petroliferous sag in the Bohai Bay Basin,and the source rocks of Paleogene Dongying and shahejie Formations were buried *** of the drillings were located at the structural high,and there were few wells that met good quality source rocks,so it is difficult to evaluate the source rocks in the study area precisely by geochemical analysis *** on the Rock-Eval pyrolysis,total organic carbon(TOC)testing,the organic matter(OM)abundance of Paleogene source rocks in the southwestern Bozhong sag were evaluated,including the lower of second member of Dongying Formation(E_(3)d2L),the third member of Dongying Formation(E_(3)d_(3)),the first and second members of shahejie Formation(E_(2)s_(1+2)),the third member of shahejie Formation(E_(2)s_(3)).The results indicate that the E_(2)s_(1+2)and E_(2)s_(3)have better hydrocarbon generative potentials with the highest OM abundance,the E_(3)d_(3)are of the second good quality,and the E_(3)d2L have poor to fair hydrocarbon generative ***,the well logs were applied to predict TOC and residual hydrocarbon generation potential(s_(2))based on the sedimentary facies classification,usingΔlogR,generalizedΔlogR,logging multiple linear regression and BP neural network *** various methods were compared,and the BP neural network method have relatively better prediction *** on the pre-stack simultaneous inversion(P-wave impedance,P-wave velocity and density inversion results)and the post-stack seismic attributes,the three-dimensional(3D)seismic prediction of TOC and s_(2)was carried *** results show that the seismic near well prediction results of TOC and s_(2)based on seismic multi-attributes analysis correspond well with the results of well logging methods,and the plane prediction results are identical with the sedimentary facies map in the study *** TOC and s_(2)values of E_(2)s_(1+2)and E_(2)s_(3)are higher than those in E_(3)d_(3)and E_(3)d_(2)L,basicall

关键词： Total organic carbon(TOC) Residual hydrocarbon generation potential(s_(2)) geophysical prediction seismic attribute Bozhong sag Bohai Bay Basin

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Burden landscape of hepatobiliary and pancreatic cancers in Chinese young adults:30 years’overview and forecasted trends

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World Journal of gastrointestinal Oncology 2024年第10期16卷 4177-4193页

作者： De-sheng Chen ze-Ping Chen Dong-Zi Zhu Lv-Xin guan Qi Zhu Yi-Chao Lou ze-Ping He Hao-Nan Chen Hong-Cheng sun Department of general surgery Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China Department of general surgery Shanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China shenzhen Institute of Translational Medicine The First Affiliated Hospital of Shenzhen UniversityShenzhen 518035Guangdong ProvinceChina Department of general surgery Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou 310016Zhejiang ProvinceChina

BACKgROUND Hepatobiliary and pancreatic(HBP)cancers impose a considerable burden on young populations(aged 15 to 49 years),resulting in a substantial number of new cases and fatalities each *** young populations,the HBP cancers shows extensive variance worldwide and the updated data in China is *** To investigate the current status,trends,projections,and underlying risk factors of HBP cancers among young populations in *** The global Burden of Disease study 2019 provided data on the annual incidence,mortality,disability-adjusted life years(DALYs),age-standardized incidence rate(AsIR),mortality rate(AsMR),and DALYs rate(AsDR)of HBP cancers in young Chinese adults between 1990 and *** trends were assessed using estimated annual percentage change and hierarchical ***-specific mortality and DALYs caused by various risks were analyzed across China and other regions,with future trends until 2035 projected using the Bayesian age-period-cohort *** From 1990 to 2019,incident cases,deaths,DALYs,AsIR,AsMR,and AsDR for liver cancer(LC)in young Chinese individuals decreased,classified into'significant decrease'***,cases of gallbladder and biliary tract cancer and pancreatic cancer rose,categorized as either'significant increase'or'minor increase'*** contribution of risk factors to mortality and DALYs for HBP tumors increased to varying *** lifestyle behaviors,such as tobacco control,weight management,alcohol moderation,and drug avoidance,could lower HBP cancers ***,except for LC in females,which is likely to initially decline slightly and then rise,the forecasting model predicted that the AsIR and AsMR for all HPB cancers subtypes by gender will increase among young *** HBP cancers burden among young adults in China is expected to increase until 2035,necessitating lifestyle interventions and targeted treatment strategies to mitigate the public health impact of these

关键词： Hepatobiliary and pancreatic cancers Burden landscape Young adults Projection China

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Chaiqin Chengqi Decoction as an adjuvant treatment for mild/moderately severe hypertriglyceridemic acute pancreatitis: A retrospective study

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World Journal of Clinical Cases 2024年第11期12卷 1918-1928页

作者： Hai-Fu Zhang ze-Xuan su Yong-Hang Feng shuo-Jun Li Bi-Yun Xie Department of Internal Medicine The First People's Hospital of FuyangHangzhou 311400Zhejiang ProvinceChina

Hypertriglyceridemia is the third leading cause of acute pancreatitis(AP),and its incidence is *** to its relatively insidious etiology,it is easy to be ignored in the early *** China,Chaiqin Chengqi Decoction(CQCQD)has long been employed for treating *** To evaluate the effectiveness of CQCQD in patients diagnosed with mild/moderately severe hypertriglyceridemic AP(HTg-AP).METHODs In this study,the clinical data of 39 patients with HTg-AP admitted from January 2019 to November 2022 were *** changes of blood lipids,gastrointestinal symptoms,and abdominal pain before and after treatment were analyzed and compared between the two *** Twenty patients were treated with the conventional HTg-AP regimen,and 19 patients were additionally treated with *** receiving treatment,the triglycerides(Tg)level of the CQCQD group was lower than that of the CQCQD group(3.14±0.25 mmol/L vs 4.96±0.47 mmol/L,Ps in the CQCQD group had more bowel movements than the control group(2.51±0.25 times vs 1.00±0.17 times,P=0.01).The gastrointestinal function of most patients returned to normal,and the acute gastrointestinal injury score was significantly lower than that of the control group(0.11±0.07 vs 0.42±0.11,PsION In patients with HTg-AP,CQCQD can significantly reduce the Tg level,shorten the recovery time of defecation,significantly improve the gastrointestinal function.

关键词： Hypertriglyceridemic acute pancreatitis Chinese medicine Chaiqin Chengqi Decoction serum lipid Triglycerides

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Ischemic colitis induced by a platelet-raising capsule: A case report

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World Journal of Clinical Cases 2024年第3期12卷 607-615页

作者： Chen-Lu Wang ze-Kun si guo-Hong Liu Chen Chen Hui Zhao Lei Li The Affiliated Hospital of shandong second Medical University School of Clinical MedicineShandong Second Medical UniversityWeifang 261000Shandong ProvinceChina Department of gastroenterology The Affiliated Hospital of Shandong Second Medical UniversityWeifang 261000Shandong ProvinceChina

BACKgROUND Ischemic colitis(IC)is also known as colon ischemia and is caused by colon vascular occlusion or nonocclusion,which results in a reduced blood supply to the colon and is not significant enough to maintain the metabolic function of cells,leading to intestinal wall *** main symptoms include abdominal pain,diarrhea,and bloody *** severe cases,intestinal gangrene,peritonitis,intestinal stenosis and even intestinal obstruction may *** induced by long-term use of certain special drugs is relatively rare in clinical *** article describes the clinical diagnosis and treatment of a typical case and provides a new treatment idea for the treatment of *** sUMMARY The patient was admitted to the hospital with"abdominal pain for half a month and bloody stool with mucous and pus for 3 d"and was diagnosed with"IC".symptomatic and supportive treatment,such as antibiotics(levofloxacin),acid inhibition and stomach protection,fluid replenishment,and intravenous nutrition,was *** patient's colonic ulcers were considered to be related to the oral administration of platelet(PLT)-raising capsules;the patient was asked to stop PLT-raising drugs for selective review via colonoscopy,and antibiotics and mesalazine enteric-coated tablets were *** the guidance of hematology consultation,60 mg of methylprednisolone was given in combination with PLT infusion to increase the *** treatment,the patient's condition stabilized,the patient’s stool turned yellow,the patient’s symptoms improved,and the patient was allowed to leave the *** PLT-raising capsules can lead to IC,so clinicians should have a full understanding of the application of these drugs in the treatment of various causes of thrombocyt-INTRODUCTION Ischemic colitis(IC)is also known as colon ischemia(CI)and is caused by colon vascular occlusion or nonocclusion,which results in a reduced blood supply to the colon;this process is not significant enough to maintai

关键词： Platelet-raising capsule Ischemic colitis Drug-related Colonic ulcer Case report

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Mode Multiplication of Cylindrical Vector Beam Using Raytracing Control

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Chinese Physics Letters 2024年第9期41卷 40-51页

作者： Jing Wang Qingji zeng Haisheng Wu Chuangxin Xie Huapeng Ye ze Dong Dianyuan Fan shuqing Chen Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518060China guangdong Provincial Key Laboratory of Optical Information Materials and Technology and Institute of Electronic Paper DisplaysSouth China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou 510006China school of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

Cylindrical vector beams(CVBs)hold significant promise in mode division multiplexing communication owing to their inherent vector mode ***,existing studies for facilitating CVB channel processing are confined to mode shift conversions due to their reliance on spin-dependent helical modulations,overlooking the pursuit of mode multiplication *** challenge lies in the multiplicative operation upon inhomogeneous vector mode manipulation,which is expected to advance versatile CVB channel switching and ***,we tackle this gap by introducing a raytracing control strategy that conformally maps the light rays of CVB from the whole annulus distribution to an annular sector *** with the multifold conformal annulus-sector mappings and polarization-insensitive phase modulations,this approach facilitates the parallel transformation of input CVB into multiple complementary components,enabling the mode multiplication conversion with protected vector *** as a demonstration,we experimentally implemented the multiplicative operation of four CVB modes with the multiplier factors of𝑁N=+2 and N=−3,achieving the converted mode purities over 94.24%and 88.37%.subsequently,200 gbit/s quadrature phase shift keying signals were successfully transmitted upon multiplicative switching of four CVB channels,with the bit-error-rate approaching 1×10−*** results underscore our strategy’s efficacy in CVB mode multiplication,which may open promising prospects for its advanced applications.

关键词： structure. multiplicative approaching

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Harpoon-shaped topological photonic crystal for on-chip beam splitter

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science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 91-98页

作者： Zhiwei guan Ruixue Dou Chuangxin Xie Tianyimei Zuo Liyu Huang Keyin Wen Chaofeng Wang Huapeng Ye Junmin Liu ze Dong Dianyuan Fan shuqing Chen Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518060China College of Physics and Engineering Technology Minzu Normal University of XingyiXingyi 562400China guangdong Provincial Key Laboratory of Optical Information Materials and Technology and Institute of Electronic Paper Displays South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou 510006China College of New Materials and New Energies Shenzhen Technology UniversityShenzhen 518118China school of information and Electronics Beijing Institute of TechnologyBeijing 100081China

The advancement of integrated optical communication networks necessitates the deployment of on-chip beam splitters for efficient signal interconnections at network ***,the pursuit of micron-scale beam splitting with large corners and reducing the device footprint to boost connection flexibility often results in phase *** mismatches,which stem from radiation modes and backward scattering,pose significant obstacles in creating highly integrated and interference-resistant *** address this,we introduce a solution based on the topological valley-contrasting state generated by photonic crystals with opposing valley Chern numbers,manifested in a harpoon-shaped structure designed to steer the splitting *** approach enables adiabatic mode field evolution over large corners,capitalizing on the robust phase modulation capabilities and topological protection provided by the subwavelength-scale valley-contrasting *** demonstration reveals that beam splitters with large corners of 60°,90°,and 120°exhibit insertion loss fluctuations below 2.7 dB while maintaining a minimal footprint of 8.8μm×8.8μ*** a practical demonstration,these devices facilitate three-channel signal connections,successfully transmitting quadrature phase shift keying signals at 3.66 Tbit/s with bit error rates below the forward error correction threshold,demonstrating performance comparable to that in defects *** harnessing the unidirectional excitation feature,we anticipate significant enhancements in the capabilities of signal distribution and connection networks through a daisy chain configuration.

关键词： channel interconnection on-chip beam splitter topological valley-contrasting state

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Animal models of hepatitis E infection: Advances and challenges

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 171-180页

作者： ze Xiang Xiang-Lin He Chuan-Wu Zhu Jia-Jia Yang Lan Huang Chun Jiang Jian Wu Chinese Consortium for the study of Hepatitis E(CCsHE) Zhejiang University school of Medicine Hangzhou 310030China Department of Infectious Diseases The Fifth People’s Hospital of SuzhouSuzhou 215007China Department of Infection Management The Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhou Municipal HospitalGusu SchoolNanjing Medical UniversitySuzhou 215008China Department of Clinical Laboratory The Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhou Municipal HospitalGusu SchoolNanjing Medical UniversitySuzhou 215008China 不详

Hepatitis E virus(HEV)is one of the leading causes of acute viral hepatitis *** most of HEV infections are asymptomatic,some patients will develop the symptoms,especially pregnant women,the elderly,and patients with preexisting liver diseases,who often experience anorexia,nausea,vom-iting,malaise,abdominal pain,and *** infection may become chronic in immunosuppressed *** addition,HEV infection can also cause several extrahepatic *** exists in a wide range of hosts in nature and can be transmitted across ***,animals susceptible to HEV can be used as *** establishment of animal models is of great significance for studying HEV transmission,clinical symptoms,extrahepatic manifestations,and therapeutic strategies,which will help us understand the pathogenesis,prevention,and treatment of hepatitis *** review summarized the animal models of HEV,including pigs,monkeys,rabbits,mice,rats,and other *** each animal species,we provided a concise summary of the HEV genotypes that they can be infected with,the cross-species transmission pathways,as well as their role in studying extrahepatic manifestations,prevention,and treatment of HEV *** advantages and disadvantages of these animal models were also *** review offers new perspectives to enhance the current understanding of the research landscape surrounding HEV animal models.

关键词： Hepatitis E virus Animal models Pathogenesis Prevention Treatment

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