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Evaluation of terrestrial radiation in the Chengdu Plain using 1/250,000-scale geochemical prospecting data

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Nuclear Science and Techniques 2017年第10期28卷 31-36页

作者： Qing-xian Zhang Jian-Kun Zhao Yi gu Liang-Quan Ge Yuan-Qing Huang Sichuan-Provincial Key Laboratory of Nuclear Technologyin Geosciences Chengdu University of TechnologyChengdu 610059China Sichuan Nuclear Geology Institute Chengdu 610061China

Based on the geochemical prospecting data, we have calculated the gamma absorbed dose rates in air 1 m above the ground surface in the Chengdu Plain, analyzed the relationship between the geological conditions and the distribution of the natural radionuclides, and preliminarily studied the influence of the geological conditions on the terrestrial radiation level in the Chengdu Plain. The result shows that the terrestrial radiation level in the Chengdu Plain is slightly lower than the average values of China and varies greatly according to the complex geological conditions.

关键词：成都平原地面辐射地球化学找矿评价天然放射性核素地质条件辐射水平普查数据

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Phosphine-Catalyzed Interrupted Morita-Baylis-Hillman Reaction and Switchable Domino Reactions of a-Substituted Activated Olefins with Formaldehyde and Mechanism Elucidation

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Chinese Journal of Chemistry 2019年第2期37卷 155-160页

作者： Jing gu Ben-xian Xiao Qin Ouyang Wei Du Ying-Chun Chen Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of PharmacySichuan UniversityChengdu 610041China College of Pharmacy Third Military Medical UniversityShapingbaChongqing 400038China

Summary of main observation and conclusion 3-Olefinic oxindoles can undergo interrupted Morita-Baylis-Hillman reaction with formaldehyde. Apart from the previous reported dephosphoration to access reductive aldol-type products, here we uncovered that completely different pathways were followed by tuning the substitutions of 3-olefinic oxin doles. In com bin ation with formalin, an unexpected domino phosphorus-ylide formation, aldol-type addition, hemeacetal formation and O-substitution process was observed to produce 1,3-dioxolane derivatives. Moreover, a switchable sequence to produce formate derivatives via a key hydride transfer process was furnished by simply replacing formalin with paraformaldehyde. Density functional theory calculations were conducted to well elucidate the catalytic reaction mechanism.

关键词： Phosphine-Catalyzed Interrupted Morita-Baylis-Hillman Reaction Switchable Domino Reactions of a-Substituted Activated Olefins Formaldehyde Mechanism Elucidation

Adaptive robust Max-SLNR precoder for MU-MIMO-OFDM systems with imperfect CSI

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Science China(Information Sciences) 2016年第6期59卷 130-143页

作者： feng SHU Juanjuan TONG Xiaohu YOU Chen gu Jiajun WU School of Electronic and Optical Engineering Nanjing University of Science and Technology National Mobile Communications Research Laboratory Southeast University Ministerial Key Laboratory of JGMT Nanjing University of Science and Technology

The accuracy of channel state information(CSI) available at a base station(BS) has a direct impact on the performance of precoding in wideband multi-user multiple input, multiple output-orthogonal frequency division multiplexing(MIMO-OFDM) systems and depends on many factors, including: the delay between estimation and beamforming at the BS(also called the CSI delay), Doppler spread, the channel estimation method used, the average transmit power of pilot symbols, and the average number of pilot symbols that must be estimated per channel parameter. In this paper, the coefficient of CSI error needed to adapt to fading channels is modeled as a function of Doppler spread, CSI delay, and signal-to-noise ratio(SNR). In terms of the Gaussian-Markov CSI error model, an adaptive robust maximum signal-to-leakage-and-noise ratio(MaxSLNR) precoder is designed to track the statistical parameters of CSI error. The Doppler spread and SNR can be obtained through real-time estimation based on orthogonal pilot patterns. Simulation results show that,compared to non-adaptive robust and non-robust precoders of Max-SLNR, the proposed adaptive robust MaxSLNR precoder performs much better in terms of bit error rate(BER). Moreover, as either the average number of training symbols per channel parameter or the average transmit power increases, the BER performance of the proposed precoder approaches that of a precoder with ideal CSI.

关键词： multiuser MIMO OFDM Max-SLNR adaptive robust precoder beamforming

AN EFFICIENT THIRD-ORDER SCHEME FOR THREE-DIMENSIONAL HYPERBOLIC CONSERVATION LAWS

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International Journal of Modeling, Simulation, and Scientific Computing 2012年第4期3卷 38-57页

作者： LI CAI JIAN-HU feng YU-feng NIE WEN-xian XIE School of Science Northwestern Polytechnical University Xi’anShaanxi 710072P.R.China College of Science Chang’an University Xi’anShaanxi 710064P.R.China

In this paper,we present a third-order central weighted essentially nonoscillatory(CWENO)reconstruction for computations of hyperbolic conservation laws in three space ***,as a Godunov-type central scheme,the CWENOtype central-upwind scheme,i.e.,the semi-discrete central-upwind scheme based on our third-order CWENO reconstruction,is developed straightforwardly to solve 3D systems by the so-called componentwise and dimensional-by-dimensional *** high resolution,the efficiency and the nonoscillatory property of the scheme can be verified by solving several numerical experiments.

关键词： Hyperbolic conservation laws CWENO reconstruction semi-discrete centralupwind scheme.

Significance of achieving carbon neutrality by 2060 on China's energy transition pathway: A multi-model comparison analysis

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Advances in Climate Change Research 2023年第1期14卷 32-42页

作者： Ling-Si KONG xian-Chun TAN Bai-He gu Hong-Shuo YAN Institutes of Science and Development Chinese Academy of SciencesBeijing 100190China School of Public Policy and Management University of Chinese Academy of SciencesBeijing 100049China Center for Carbon Neutrality Strategy Institutes of Science and DevelopmentChinese Academy of SciencesBeijing 100190China

China has proposed to achieve carbon neutrality by *** previous studies have assessed net-zero emissions pathways in China,the diversity observed in these studies in terms of model construction and parameter setting has led to inconsistent conclusions on some key issues,such as energy *** study employs a multi-model comparison method to examine the significance of China's carbon neutrality target on its energy systems by assessing 67 carbon neutrality scenarios in China that are collected from the ADVANCE database,and identifying the differences between energy transition pathways under BEF60 scenarios(*** realising carbon neutrality by 2060)and AFT60 scenarios(*** realising carbon neutrality after 2060).Results show that China needs a larger deployment of low-carbon electricity,a higher electrification rate and more carbon sequestration amount under BEF60 scenarios than those under AFT60 ***,the magnitude of the difference between the two categories of scenarios varies significantly in terms of different outcome *** that present significant disparities include the deployment scale of solar power(increasing by 160%),the electrification rate of the building sector(increasing by 27%)and the carbon sequestration amount of biomass power with carbon capture and storage(increasing by 380%).In addition,this study selects six indicators to present the technological and economic characteristics of various energy systems of China at the point of net-zero *** the relationships between characteristics,this research identifies the common features among various net-zero energy systems.A great share of non-biomass renewable power generation is always associated with a relatively high per capita energy use,implying that high renewables penetration may relax restrictions on energy consumption,which should be addressed for China when making efforts to promote energy transition.

关键词： Carbon neutrality Multi-model comparison analysis Energy transition Technology option Common feature

SYMPLECTIC STRUCTURE OF POISSON SYSTEM

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Applied Mathematics and Mechanics(English Edition) 2005年第11期26卷 1484-1490页

作者：孙建强马中骐田益民秦孟兆 gu Yuan-xian Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 P. R. China Institute of Applied Physics and Computational Mathematics Beijing 100088 P. R. China Institute of Software Chinese Academy of Sciences Beijing 100080 P. R. China Institute of Computational Mathematics Chinese Academy of Sciences Beijing 100080 P. R. China 不详

When the Poisson matrix of Poisson system is non-constant, classical symplectic methods, such as symplectic Runge-Kutta method, generating function method, cannot preserve the Poisson structure. The non-constant Poisson structure was transformed into the symplectic structure by the nonlinear transform. Arbitrary order symplectic method was applied to the transformed Poisson system. The Euler equation of the free rigid body problem was transformed into the symplectic structure and computed by the mid-point scheme. Numerical results show the effectiveness of the nonlinear transform.

关键词： Poisson system nonlinear transformation symplectic method rigid body problem

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A New Method for Phase Retrieval in the Optical System

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Chinese Physics Letters 1998年第1期15卷 24-26页

作者： CONG Wen-xiang CHEN Nan-xian gu Ben-Yuan Institute of Applied Physics Beijing University of Science and TechnologyBeijing 100083 Institute of Physics Chinese Academy of SciencesBeijing 100080

In this letter,a new recursive algorithm to implement phase retrieval from two intensities in the two-dimensional Fourier transform domain is *** terms of the cascading property and additivity of the order of the fractional Fourier transform,a set of convolution equations is exactly *** recursive algorithm,these equations can be easily *** approach simplifies significantly computational manipulations comparing with conventional iterative algorithms and does not need initial phase distribution.

关键词： recursive letter equations

Metastasis of esophageal squamous cell carcinoma to the thyroid gland with widespread nodal involvement: A case report

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World Journal of Clinical Cases 2020年第19期8卷 4588-4594页

作者： Xing Zhang Xin gu Jia-Gen Li xian-Jie Hu Department of Thyroid and Breast Surgery The Affiliated People's Hospital of Ningbo UniversityNingbo 315040Zhejiang ProvinceChina Department of Pathology The Affiliated People's Hospital of Ningbo UniversityNingbo 315040Zhejiang ProvinceChina

BACKGROUND Esophageal cancer is one of the most common causes of cancer-related *** patients with esophageal cancer have distant metastases at the time of diagnosis,but metastasis to the thyroid gland(MTG)and multifocal thyroid lesions alone are extremely *** SUMMARY In this case report,we present a case of a 69-year-old male with esophageal *** patient visited our hospital for a routine body check-up,which revealed multifocal nodules in his thyroid lobes and enlarged cervical lymph nodes.A fine needle aspiration biopsy showed malignancies in both thyroid lesions and lymph *** patient was initially diagnosed with primary bilateral thyroid cancer that spread to his lymph nodes,and a total thyroidectomy was *** histology showed MTG and therefore,a diagnostic work-up was implemented to determine the primary tumor.A fluorine-18-deoxyglucose positron emission tomography scan showed that the lower part of the esophagus and the lymph nodes in the neck,chest,and abdomen were *** esophagogastroscopy and corresponding pathology revealed distal esophageal squamous cell *** esophageal MTG diagnosis was confirmed with pathological *** This case report highlights the difficulty in diagnosing esophageal *** may have no malignancy history and be *** diagnostic procedures are necessary after MTG is confirmed by cytology or histology,and the final diagnosis should be made according to the identification of the primary malignancy combined with pathological immunohistochemistry findings.

关键词： Esophageal squamous cell carcinoma Metastasis Thyroid gland Thyroidectomy Lymph nodes Case report

Cytoplasmic FKBPs are involved in molting and metamorphosis through regulating the nuclear localization of EcR

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Insect Science 2024年第3期31卷 759-772页

作者： xian Zhang Qiao-Ran Wang Qian Wu Jun gu Li-Hua Huang guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology School of Life SciencesSouth China Normal UniversityGuangzhouChina guangmeiyuan R&D Center Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied TechnologySouth China Normal UniversityMeizhouChina

Molting and metamorphosis are important physiological processes in insects that are tightly controlled by ecdysone receptor(EcR)through the 20-hydroxyecdysone(20E)signaling *** is a steroid nuclear receptor(SR).Several FK506-binding proteins(FKBPs)have been identified from the mammal SR complex,and are thought to be involved in the subcellular trafficking of ***,their roles in insects are poorly *** explore whether FKBPs are involved in insect molting or metamorphosis,we injected an FKBP inhibitor(FK506)into a lepidopteran insect,Spodoptera litura,and found that molting was inhibited in 61.11%of the larvae,and that the time for larvae to pupate was significantly extended.A total of 10 FKBP genes were identified from the genome of *** and were clustered into 2 distinct groups,according to their subcellular localization,with FKBP13 and FKBP14 belonging to the endoplasmic reticulum(ER)group and with the other members belonging to the cytoplasmic(Cy)*** the CyFKBPs were significantly upregulated in the prepupal or pupal stages,with the opposite being observed for the ER group ***506 completely blocked the transfer of EcR to the nucleus under 20E induction,and significantly downregulated the transcriptional expression of many 20E signaling genes.A similar phenomenon was observed after RNA interference of2 CyFKBPs(FKBP45 and FKBP12b),but not for *** together,our data indicate that the cytoplasmic FKBPs,especially FKBP45 and FKBP12b,mediate the nuclear localization of EcR,thereby regulating the 20E signaling and ultimately affecting molting and metamorphosis in insects.

关键词： EcR FKBP metamorphosis molting RNAi subcellular localization