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Tomographic Study of Ionospheric Effects Associated with a Solar Eclipse

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wuhan University Journal of Natural Sciences 2003年第2A期8卷 399-404页

作者： wu xiong-bin, Xu Ji-sheng, Ma Shu-ying, Tian MaoSchool of Electronic Information, wuhan University, wuhan 430072, Hubei, China School of Electronic Information Wuhan University Wuhan Hubei China

This paper studies the ionospheric effects associated with the solar eclipse of October 24th, 1995 by means of Computerized Ionospheric Tomography (CIT). Since the reconstructed profiles from experimental CIT are sporadically located in time, a time domain interpolation method based on Singular Value Decomposition (SVD) technique is proposed and applied to extract the ionospheric effects. The effects can be extracted by comparison analysis between the interpolated CIT profiles of the eclipse days and that of the reference day that are time-aligned. A series of figs have been obtained showing the attenuation of photonization effect at low altitudes and the weakening of plasma’s transportation process at high altitudes, etc. The photonization effect recovered to normal level soon after the last contact. The maximum electron density diminishing is observed about 2 h after the eclipse maximum and the effects seem vanished in the hours followed. Analysis on vertical TEC’s latitudinal-temporal variation gives similar conclusions.

关键词： ionosphere solar eclipse tomography total electron content international reference ionosphere

Boosting thermal stability and crystallization of closed-loop-recyclable biodegradable poly(p-dioxanone) by end-group regulation

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Science China Chemistry 2024年第2期67卷 642-651页

作者： Jin Lei Zhu-Xin Gui Wan-Ting xiong Gang wu Si-Chong Chen Yu-Zhong Wang The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu610064China

A chemically closed-loop-recyclable biodegradable polymer,poly(p-dioxanone)(PPDO),is one of the ideal candidates for single-use plastic products due to its suitability for different application ***,when PPDO wastes can be collected,its monomer p-dioxanone(PDO) will be obtained through chemical recycling of these wastes;when cannot be collected,the wastes are able to be biodegraded into harmless ***,unsatisfied thermal stability and low crystallization rate of PPDO restrict its wider ***,based on end-group regulation,we simultaneously realized the significant enhancement of thermal stability and crystallization of PPDO through the simple melt processing with tributyl phosphite(TBP) or triphenyl phosphite(TPP).The model reactions were conducted to investigate the reaction mechanism and theoretical products during the preparation of PPDO/phosphite *** kinds of phosphites were proved to act as the end-capped reagent and chain extender in the melt processing,while TBP presented better *** a result,the activation energy of thermal decomposition was largely elevated,and the unprecedented T_(5%)(the temperature at a weight loss of 5%) and Tmax(the temperature at a maximum rate of weight loss) of PPDO were obtained,i.e.,T_(5%)of ~330 ℃ and Tmaxof ~385 ℃ in N_(2) atmosphere,T_(5%)of ~240 ℃ and Tmaxof ~317 ℃ in air atmosphere,***,the increased crystallization rate,crystallinity,crystalline orderliness,and realizable monomer recovery(yield >90%,purity >99.9%) of PPDO/phosphite compounds were confirmed.

关键词： poly(p-dioxanone) phosphite thermal stability crystallization end-group regulation

A randomized, controlled, multicenter contraceptive efficacy clinical trial of the intravas device, a nonocclusive surgical male sterilization

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Asian Journal of Andrology 2014年第3期16卷 432-436页

作者： Wen-Hong Lu Xiao-Wei Liang Yi-Qun Gu Wei-xiong wu Li-Wei Bo Tian-Gui Zheng Zhen-Wen Chen Key Laboratory of Male Reproductive Health National Health and Family Planning Commission National Research Institute for Family Planning and WHO Collaborating Centre for Research in Human Reproduction Beijing Institute for Family Planning of Guangzhou city Guangzhou Institute for Family Planning of Henan Province Zhengzhou Institute for Family Planning of Putian City Putian China.

Because of unavoidable complications of vasectomy, this study was undertaken to assess the efficacy and safety of male sterilization with a nonobstructive intravas device （IVD） implanted into the vas lumen by a mini-surgical method compared with no-scalpel vasectomy （NSV）. IVDs were categorized into two types： IVD-B has a tail used for fixing to the vas deferens （fixed wing） whereas IVD-A does not. A multicenter prospective randomized controlled clinical trial was conducted in China. The study was comprised of 1459 male volunteers seeking vasectomy who were randomly assigned to the IVD-A （n = 487）, IVD-B （n = 485） or NSV （n = 487） groups and underwent operation. Follow-up included visits at the 3rd-6TM and 12~ postoperative months, The assessments of the subjects involved regular physical examinations （including general and andrological examinations） and semen analysis. The subjects＇ partners also underwent monitoring for pregnancy by monthly interviews regarding menstruation and if necessary, urine tests, There were no significant differences in pregnancy rates （0.65% for IVD-A, 0 for IVD-B and 0.21% for NSV） among the three groups （P 〉 0.05）. The cumulative rates of complications at the 12th postoperative month were zero, 0.9% and 1.7% in the three groups, respectively. In conclusion, IVD male sterilization exhibits a low risk of long-term adverse events and was found to be effective as a male sterilization method, similar to the NSV technique. IVD male sterilization is expected to be a novel contraceptive method.

关键词： complication male sterilization nonobstructive intravas device no-scalpel vasectomy

Management of centrally located hepatocellular carcinoma:Update 2016

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World Journal of Hepatology 2017年第13期9卷 627-634页

作者： Wei-Bo Yu Andrew Rao Victor Vu Lily Xu Jian-Yu Rao Jian-xiong wu Department of Pathology and Laboratory Medicine David Geffen School of MedicineUniversity of California at Los Angeles the College of Letters and Science University of California at Davis Chemistry Department Wellesley College Department of Hepatobiliary Surgery National Cancer Center/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical College

Centrally located hepatocellular carcinoma(HCC)is sited in the central part of the liver and adjacent to main hepatic vascular *** special location is associated with an increase in the difficulty of surgery,aggregation of the recurrence disease,and greater challenge in disease *** review summarizes the evolution of our understanding for centrally located HCC and discusses the development of treatment strategies,surgical approaches and recurrence prevention *** improve patient survival,a multi-disciplinary modality is greatly needed throughout the whole treatment period.

关键词： Centrally located hepatocellular carcinoma Hepatectomy Combined treatment Hepatic vascular occlusion

Raising the capacity of lithium vanadium phosphate via anion and cation co-substitution

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Science China Chemistry 2020年第2期63卷 203-207页

作者： Xian-Xiang Zeng Hui Chen Gang Guo Sheng-Yi Li Jin-Ying Liu Qiang Ma Guote Liu Ya-Xia Yin xiong-Wei wu Yu-Guo Guo College of Science Hunan Agricultural UniversityChangsha 410128China Laboratory of Molecular Nanostructure and Nanotechnology Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China College of Electrical Engineering and Automation Foshan UniversityFoshan 528225China

The pursuit for batteries with high specific energy provokes the research of high-voltage/capacity cathode materials with superior stability and safety as the alternative for lithium iron ***,using the sol-gel method,a lithium vanadium phosphate with higher average discharge voltage(3.8 V,***+/Li) was obtained from a single source for Mg2+ and Cl-co-substitution and uniform carbon coating,and a nearly theoretical capacity(130.1 mA h g^-1) and outstanding rate performance(25 C) are acquired together with splendid capacity retention(80%) after 650 *** work reveals that the well-sized anion and cation substitution and uniform carbon coating are of both importance to accelerate kinetic performance in the context of nearly undisturbed crystal structure for other analogue *** is anticipated that the electrochemistry comprehension will shed light on preparing cathode materials with high energy density in the future.

关键词： polyanion cathode ion substitution carbon coating high rate theoretical capacity

Prediction on hot deformation behavior of spray-formed 7055 aluminum alloy via phenomenological models

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Transactions of Nonferrous Metals Society of China 2018年第8期28卷 1484-1494页

作者： Xiang-dong WANG Qing-lin PAN Shang-wu xiong Li-li LIU Yuan-wei SUN Wei-yi WANG School of Materials Science and Engineering Central South UniversityChangsha 410083China School of Light Alloys Research Institution Central South UniversityChangsha 410083China

Hot compression tests in the temperature range of 340-450 ℃ and strain rate range of 0.001-1 s^-1 of spray-formed 7055 aluminum alloy were carried out to study its hot deformation behavior. Three phenomenological models including Johnson-Cook, modified Fields-Backofen and Arrhenius-type were introduced to predict the flow stresses during the compression process. And then, a comparative predictability of the phenomenological models was estimated in terms of the relative errors, correlation coefficient（R）, and average absolute relative error（AARE）. The results indicate that Johnson-Cook model and modified Fields-Backofen model cannot well predict the hot deformation behavior due to the large deviation in the process of line regression fitting. Arrhenius-type model obtains the best fit through combining the effect of strain rate and temperature.

关键词： spray-formed 7055 aluminum alloy hot deformation behavior phenomenological models statistical analyses

Synergistic Promotion of Electrical, Mechanical and Thermal Properties for Silicone Rubber-based Field Grading Material via Compound Modification

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 337-350页

作者： Jiale wu Yangzhi Gong Peiqi xiong Zexi Xing Xiaofeng Xue Xiao Yang Boyang Shen Xingming Bian State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University102206 BeijingChina State Grid Fuzhou Electric Power Supply Company Fuzhou 350009Fujian ProvinceChina Electrical Engineering Division University of CambridgeCambridge CB30FAUK

Use of nonlinearconductive SiC/silicone rubber(SR)field grading material(FGM)can improve the local field concentration of composite *** large volume fraction and large-size SiC particles(SiCp)into SR can obtain a good field grading effect,but it is accompanied by the deterioration of mechanical *** SiC with different shapes can solve this *** incorporating one-dimensional SiC whiskers(SiCw)to synergize with granular SiCp,SiC/SR FGM with better field-dependent conductivity,mechanical properties and thermal conductivity than large-size SiCp and large volume fraction filling case can be obtained by using smaller size SiCp and lower filling *** simulations of 500 kv line insulators show that the modified SiC/SR FGM can reduce the maximum field strength along the insulator surface and at sheath-core rod interfaces by 55%and 71.4%,*** combined application of FGM and grading ring can achieve a complementary *** FGM to partially replace the role of the grading rings,the field strength indicators can still meet the operational requirements after the tube radius and shielding depth of the grading rings at both ends are reduced by 36.2%and 40%separately,which is a benefit to alleviating the problems of high weight and large volume faced by traditional field grading methods.

关键词： Compound modification electric field regulation field grading material field-dependent conductivity mechanical properties thermal conductivity

Evolution of Cenozoic sedimentary architecture in Central and Southern South China Sea basins

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Journal of Palaeogeography 2024年第1期13卷 35-53页

作者： wu Tang Xiao-Jun Xie Yi-Bo Wang Lian-Qiao xiong Jia Guo Xin Li China National Offshore Oil Corporation Research Institute Beijing 100028China

The Central and Southern South China Sea(CSSCS) has a complex tectonic dynamic background and abundant oil and gas resources, which has always been a hot topic of academic and industrial ***, systematic analyses are still lacking regarding its sediment filling structure and evolution, mostly due to limited borehole penetration and poor quality of seismic reflection data for deeply buried sequences. No consensus has been reached yet on the sedimentary infilling processes, which impeded the reconstruction of the palaeogeography of Southeast Asia and the oil-and-gas exploration undertakings. Here, we illustrate the Cenozoic sedimentary evolution of the CSSCS region by synthesizing relevant data from previous literature and our own observations and displaying the evolution of depositional systems in sequential reconstructions. Besides, the controlling factors of preferred sedimentary scenarios in the CSSCS incorporate the latest interpretations of the spreading of South China Sea(SCS) as well as the demise of the hypothetical Proto-South China Sea(PSCS). The results show that there are three types of sedimentary basins in the CSSCS(foreland,strike-slip, and rift basins) with different sedimentary filling structures. The foreland basins formed a depositional pattern of ‘transition from deep water to shallow water environments', dominated by deep-water depositional systems which were formed before the Early Oligocene with submarine fans developed. Later,the foreland basins were gradually dominated by shallow-water depositional systems with deltas and shallow marine facies. The strike-slip basins showed the depositional architecture of ‘transition from lake to marine environments', i.e. the basins were dominated by lacustrine deposits during the Eocene and evolved into the marine depositional environment since Oligocene with delta developed in the western part of the basin. The depositional evolution of rift basins illustrated the characteristics of 'transiti

关键词： Central and Southern South China Sea Sedimentary filling Main controlling factors Proto-South China Sea South China Sea

Evaluation of molecular residual disease in operable non-small cell lung cancer with gene fusions, MET exon skipping or de novo MET amplification

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FRONTIERS OF MEDICINE 2024年第4期18卷 735-743页

作者： Fu, Rui xiong, Yuanyuan Cai, Miao Li, Fang Chen, Rongrong wu, Yilong Zhong, Wenzhao South China Univ Technol Sch Med Guangzhou 510006 Peoples R China South China Univ Technol Guangdong Acad Med Sci Guangdong Prov Peoples Hosp Guangdong Lung Canc InstGuangdong Prov Key Lab Tr Guangzhou 510080 Peoples R China Geneplus-Beijing Beijing 102206 Peoples R China

Gene fusions and MET alterations are rare and difficult to detect in plasma samples. The clinical detection efficacy of molecular residual disease (MRD) based on circulating tumor DNA (ctDNA) in patients with non-small cell lung cancer (NSCLC) with these mutations remains unknown. This prospective, non-intervention study recruited 49 patients with operable NSCLC with actionable gene fusions (ALK, ROS1, RET, and FGFR1), MET exon 14 skipping or de novo MET amplification. We analyzed 43 tumor tissues and 111 serial perioperative plasma samples using 1021- and 338-gene panels, respectively. Detectable MRD correlated with a significantly higher recurrence rate (P < 0.001), yielding positive predictive values of 100% and 90.9%, and negative predictive values of 82.4% and 86.4% at landmark and longitudinal time points, respectively. Patients with detectable MRD showed reduced disease-free survival (DFS) compared to those with undetectable MRD (P < 0.001). Patients who harbored tissue-derived fusion/MET alterations in their MRD had reduced DFS compared to those who did not (P = 0.05). To our knowledge, this is the first comprehensive study on ctDNA-MRD clinical detection efficacy in operable NSCLC patients with gene fusions and MET alterations. Patients with detectable tissue-derived fusion/MET alterations in postoperative MRD had worse clinical outcomes.

关键词： ctDNA molecular residual disease operable NSCLC gene fusion MET exon skipping MET amplification MUTATIONS CTDNA