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Ultrasound-guided stellate ganglion blockade: an appealing tactic for cardiac electrical storm

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Journal of Geriatric Cardiology 2023年第5期20卷 376-382页

作者： Zi-Hao LAI Li-hui zheng Yan YAO Arrhythmia Center Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Ventricular arrhythmia(VA)is a life-threatening cardiac *** VA occurs three times or more within 24 h and interventions are required,it is defined as an electrical storm(ES)characterized by refractoriness and recurrence.[1]For patients with implantable cardioverter defibrillator(ICD),the notion is redefined as no fewer than three appropriate and separate(at least 5 min for each interval)ICD interventions given within 24 h.

关键词： cardiac storm electrical

Palladium-catalyzed oxidative cyclopropanation of enamides and norbornenes initiated by C–H activation

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Science China Chemistry 2018年第6期61卷 695-701页

作者： Ming Chen Mi-Na Zhao Yao-Du Zhang Zhi-hui Ren zheng-hui Guan Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education Department of Chemistry & Materials Science Northwest University Shaanxi Key Laboratory of Phytochemistry College of Chemistry and Chemical Engineering Baoji University of Arts and Sciences

A novel palladium-catalyzed oxidative cyclopropanation of enamides and norbornenes has been developed. The reaction proceeded through palladium-catalyzed vinyl C–H bond activation of enamides followed by two migratory insertions, β-(N)H elimination and hydrolyzation cascade steps. The reaction tolerates a range of functional groups and provides an effective method for the synthesis of cyclopropane-fused norbornanes in good yields under mild conditions.

关键词： palladium-catalyzed cyclopropanation C–H activation enamides norbornenes

Unraveling the stabilization mechanism of solid electrolyte interface on ZnSe by rGO in sodium ion battery

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Journal of Energy Chemistry 2021年第3期30卷 124-130页

作者： Shuang Men hui zheng Dejun Ma Xiaolian Huang Xiongwu Kang School of Environment and Energy South China University of TechnologyGuangzhou 510006GuangdongChina Department of Chemical Engineering Northwest UniversityXi'an 710069ShaanxiChina School ofPhamacy Guangdong Pharmaceutical UniversityGuangzhou 510006GuangdongChina College of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou 510006GuangdongChina

Transition metal selenides have been widely studied as anode materials of sodium ion batteries(SIBs),however,the investigation of solid-electrolyte-interface(SEI)on these materials,which is critical to the electrochemical performance of SIBs,remains at its *** in this paper,ZnSe@C nanoparticles were prepared from ZIF-8 and the SEI layers on these electrodes with and without reduced graphene oxide(rGO)layers were examined in details by X-ray photoelectron spectroscopies at varied charged/discharged *** is observed that fast and complicated electrolyte decomposition reactions on ZnSe@C leads to quite thick SEI film and intercalation of solvated sodium ions through such thick SEI film results in slow ion diffusion kinetics and unstable electrode ***,the presence of rGO could efficiently suppress the decomposition of electrolyte,thus thin and stable SEI film was ***@C electrodes wrapped by rGO demonstrates enhanced interfacial charge transfer kinetics and high electrochemical performance,a capacity retention of 96.4%,after 1000 cycles at 5 A/*** study might offer a simple avenue for the designing high performance anode materials through manipulation of SEI film.

关键词： ZIF-8 Zinc selenide Transition metal selenide Reduced graphene oxide XPS Solid electrolyte interface Sodium ion batteries

Numerical study of the effects of local atmospheric circulations on a pollution event over Beijing–Tianjin–Hebei, China

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Journal of Environmental Sciences 2015年第4期27卷 9-20页

作者： Yucong Miao Shuhua Liu Yijia zheng Shu Wang Bicheng Chen hui zheng Jingchuan Zhao Department of Atmospheric and Oceanic Sciences School of Physics Peking University Department of Meteorology The Pennsylvania State University University Park Key Laboratory of Regional Climate–Environment Research for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences Department of Atmospheric Sciences Yunnan University

Currently, the Chinese central government is considering plans to build a trilateral economic sphere in the Bohai Bay area, including Beijing, Tianjin and Hebei（BTH）, where haze pollution frequently occurs. To achieve sustainable development, it is necessary to understand the physical mechanism of the haze pollution there. Therefore, the pollutant transport mechanisms of a haze event over the BTH region from 23 to 24 September 2011 were studied using the Weather Research and Forecasting model and the FLEXible-PARTicle dispersion model to understand the effects of the local atmospheric circulations and atmospheric boundary layer structure. Results suggested that the penetration by sea-breeze could strengthen the vertical dispersion by lifting up the planetary boundary layer height（PBLH） and carry the local pollutants to the downstream areas; in the early night, two elevated pollution layers（EPLs） may be generated over the mountain areas： the pollutants in the upper EPL at the altitude of 2–2.5 km were favored to disperse by long-range transport, while the lower EPL at the altitude of 1 km may serve as a reservoir, and the pollutants there could be transported downward and contribute to the surface air *** intensity of the sea–land and mountain–valley breeze circulations played an important role in the vertical transport and distribution of pollutants. It was also found that the diurnal evolution of the PBLH is important for the vertical dispersion of the pollutants,which is strongly affected by the local atmospheric circulations and the distribution of urban areas.

关键词： Air pollution Sea–land breeze circulation Mountain–valley breeze circulation WRF model FLEXPART model

Improving throughput in SWIPT-based wireless multirelay networks with relay selection and rateless codes

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Digital Communications and Networks 2024年第4期10卷 1131-1144页

作者： Gaofei Huang Qihong Zhong hui zheng Sai Zhao Dong Tang The Faculty of Electronics and Communication Engineering Guangzhou UniversityGuangzhou510006China Research Institute of China Telecom Co.Ltd Guangzhou510630China

This paper studies a dual-hop Simultaneous Wireless Information and Power Transfer(SWIPT)-based multi-relay network with a direct *** achieve high throughput in the network,a novel protocol is first developed,in which the network can switch between a direct transmission mode and a Single-Relay-Selection-based Cooperative Transmission(SRS-CT)mode that employs dynamic decode-and-forward relaying accomplished with Rateless Codes(RCs).Then,under this protocol,an optimization problem is formulated to jointly optimize the network operation mode and the resource allocation in the SRS-CT *** formulated problem is difficult to solve because not only does the noncausal Channel State Information(CSI)cause the problem to be stochastic,but also the energy state evolution at each relay is complicated by network operation mode decision and resource *** that noncausal CSI is available,the stochastic optimization issue is first to be addressed by solving an involved deterministic optimization problem via dynamic programming,where the complicated energy state evolution issue is addressed by a layered optimization ***,based on a finite-state Markov channel model and assuming that CSI statistical properties are known,the stochastic optimization problem is solved by extending the result derived for the noncausal CSI case to the causal CSI ***,a myopic strategy is proposed to achieve a tradeoff between complexity and performance without the knowledge of CSI statistical *** simulation results verify that our proposed SRS-and-RC-based design can achieve a maximum of approximately 40%throughput gain over a simple SRS-and-RC-based baseline scheme in SWIPT-based multi-relay networks.

关键词： Simultaneous wireless information and power transfer Energy harvesting Relay networks Throughput maximization

Lipase immobilized on HOOC-MCF:A highly enantioselective catalyst for transesterification resolution of (R,S)-1-phenylethanol

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Chinese Chemical Letters 2007年第8期18卷 929-932页

作者： Ping Xue Xiang hui Yan zheng Wang Key Laboratory of Energy Resources and Chemical Engineering Ningxia University Yinchuan 750021 China

Pseudomonas cepacia lipase （PSL） immobilized on the carboxyl-functionalized meso-cellular foams （HOOC-MCF） was used for the transesterification resolution of （R,S）-l-phenylethanol in organic solvent. The results showed that the ee value of （S）-1- phenylethanol and （R）-1-phenylethyl acetate reached 99% with 50% conversion of 1-phenylethanol using toluene as solvent. Furthermore, it was found that PSL/HOOC-MCF exhibited high enantioselectivity in organic solvent with log P ≤ 2 such as toluene and hexane.

关键词： Immobilized lipase Enantioselectivity Chiral resolution 1-Phenylethanol

A Multi-Scale Urban Atmospheric Dispersion Model for Emergency Management

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Advances in Atmospheric Sciences 2014年第6期31卷 1353-1365页

作者： MIAO Yucong LIU Shuhua zheng hui zheng Yijia CHEN Bicheng WANG Shu Department of Atmospheric and Oceanic Sciences School of Physics Peking University Department of Meteorology The Pennsylvania State University University Park Pennsylvania 16802 USA

To assist emergency management planning and prevention in case of hazardous chemical release into the atmosphere,especially in densely built-up regions with large populations,a multi-scale urban atmospheric dispersion model was *** numerical dispersion experiments,at horizontal resolutions of 10 m,50 m and 3000 m,were performed to estimate the adverse effects of toxic chemical release in densely built-up *** multi-scale atmospheric dispersion model is composed of the Weather Forecasting and Research （WRF） model,the Open Source Field Operation and Manipulation software package,and a Lagrangian dispersion *** of the adverse health effects of these chemical release events are given by referring to the *** Protection Agency＇s Acute Exposure Guideline *** wind fields of the urban-scale case,with 3 km horizontal resolution,were simulated by the Beijing Rapid Update Cycle system,which were utilized by the WRF *** sub-domain-scale cases took advantage of the computational fluid dynamics method to explicitly consider the effects of *** was found that the multi-scale atmospheric dispersion model is capable of simulating the flow pattern and concentration distribution on different scales,ranging from several meters to kilometers,and can therefore be used to improve the planning of prevention and response programs.

关键词： WRF model OpenFOAM AEGLs multi-scale simulation

Advances of biomarkers in nasopharyngeal carcinoma’s early detection

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Science Bulletin 2024年第2期69卷 141-145页

作者： Xiao-hui zheng Allan Hildesheim Wei-Hua Jia State Key Laboratory of Oncology in South China Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060China Costa Rican Agency for Biomedical Investigation INCIENSA FoundationSan Jose 10108Costa Rica

Nasopharyngeal carcinoma(NPC),a highly invasive and metastatic cancer,is widely prevalent in South China,Southeast Asia,and North *** patients with stages I and II are often ***,NPC patients are usually diagnosed with advanced-stage(stages III and IV)at their first *** of NPC at early stage is the key to improve the survival of ***-Barr virus(EBV)plays an essential role in NPC occurrence in endemic ***-based biomarkers,including EBV antibody in serum and EBV DNA in plasma,have been specifically proposed for NPC early ***,we summarize recent advances in biomarkers for the early detection of NPC.

关键词： patients nasopharyngeal Nasopharyngeal

Synthesis of azo derivatives of 4-aminosalicylic acid

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Chinese Chemical Letters 2007年第6期18卷 639-642页

作者： zheng Bao Zhao hui Xia zheng Yuan Gui Wei Jiang Liu College of Pharmacy Shanxi Medical University Taiyuan 030001 China First Clinical College Shanxi Medical University Taiyuan 030001 China

For searching a better 4-aminosalicylic acid derivative with higher activity and less side effects against the inflammatory bowel disease, 4-aminosalicylic acid (4-ASA) was protected by benzyloxycarbonyl and acetyl, respectively. The resultant was hydrogenized to remove protective group of amino group, then the product was reacted with NaNO2 to give diazonium salt, which was conjugated with salicylic acid, hydroxybenzene, N-salicyloyl glycine acid to get azo derivatives of 4-ASA. The azo derivatives were hydrolyzed under the alkaline condition to get the target products. All compounds were characterized by FT-IR, (1)H NMR, (13)C NMR spectra in details. New derivatives of 4-ASA were characterized. The synthetic route was reasonable and feasible.

关键词： 4-Aminosalicylic acid Azo derivatives of 4-aminosalicylic acid Inflammatory bowel disease