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Mixed Binder Carbon Paste Electrode for Quantitation of Isoniazid in Serum

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Chemical Research in Chinese Universities 1993年第4期9卷 303-308页

作者： ZHANG Zheng-Qi, CHEN sheng-zong, li Ning-Huai and ZHANG Hong (Department of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082)

This paper covers the construction and behaviour of a mixed binder carbon paste electrode system appropriate for the cathodic stripping voltammetric quantitation of iso-niazid. The mixed binder consisted of glycerol and liquid paraffin. At the mixed binder carbon paste electrodes in a pH 3.0 buffer solution, isoniazid showed two sensitive cathodic stripping voltammetric wave at-0. 75 V (p1) and-0. 88 V (p2) , respectively. The p2 can be used for the determination of trace amounts of isoniazid, the linear range of the peak current to the isoniazid concentration being from 5. 0×10-7 to 5.0×10-5 mol/L, and the limit of detection being 1. 0×10-7 mol/L with a relative standard deviation of 6. 0%(n=10). The proposed method was directly used to determine the drug in blood serum without the pretreatment of blood serum.

关键词： Carbon paste electrode Isoniazid Stripping voltammetry

Centered Waves for the Two-dimensional Pseudo-Steady van der Waals Gas Satisfied Maxwell's Law Around a Sharp Corner

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Chinese Annals of Mathematics,Series B 2024年第04期45卷 537-554页

作者： Shuangrong li Wancheng sheng Department of Mathematics Shanghai University Shanghai 200444 China Department of Mathematics Zhejiang University of Science and Technology Department of Mathematics Newtouch Center for Mathematics of Shanghai University Shanghai University

In this paper, the authors study the centered waves for the two-dimensional(2D for short) pseudo-steady supersonic flow with van der Waals gas satisfied Maxwell's law around a sharp corner. In view of the initial value of the specific volume and the properties of van der Waals gas, the centered waves at the sharp corner are constructed by classification. It is shown that the supersonic incoming flow turns the sharp corner by a centered simple wave or a centered simple wave with right-contact discontinuity or a composite wave(jump-fan, fan-jump or fan-jump-fan), or a combination of waves and constant state. Moreover, the critical angle of the sharp corner corresponding to the appearance of the vacuum phenomenon is obtained.

关键词： Centered simple wave Composite wave Two-dimensional Euler equations Van der Waals gas

Incorporating contextual evidence to improve implicit discourse relation recognition in Chinese

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Frontiers of Computer Science 2024年第3期18卷 91-104页

作者： sheng XU Peifeng li Qiaoming ZHU School of Computer Science and Technology Soochow UniversitySuzhou 215000China

The discourse analysis task,which focuses on understanding the semantics of long text spans,has received increasing attention in recent *** a critical component of discourse analysis,discourse relation recognition aims to identify the rhetorical relations between adjacent discourse units(e.g.,clauses,sentences,and sentence groups),called arguments,in a *** works focused on capturing the semantic interactions between arguments to recognize their discourse relations,ignoring important textual information in the surrounding ***,in many cases,more than capturing semantic interactions from the texts of the two arguments are needed to identify their rhetorical relations,requiring mining more contextual *** this paper,we propose a method to convert the RST-style discourse trees in the training set into dependency-based trees and train a contextual evidence selector on these transformed *** this way,the selector can learn the ability to automatically pick critical textual information from the context(i.e.,as evidence)for arguments to assist in discriminating their *** we encode the arguments concatenated with corresponding evidence to obtain the enhanced argument ***,we combine original and enhanced argument representations to recognize their *** addition,we introduce auxiliary tasks to guide the training of the evidence selector to strengthen its selection *** experimental results on the Chinese CDTB dataset show that our method outperforms several state-of-the-art baselines in both micro and macro F1 scores.

关键词： discourse parsing discourse relation recognition contextual evidence selection

Traveling Wave Characteristics Based Pilot Protection Scheme for Hybrid Cascaded HVDC Transmission line

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 971-980页

作者： Dalin Mu sheng lin Xiaopeng li the School of Electrical Engineering Southwest Jiaotong UniversityChengdu 611756China the State Grid Sichuan Electric Power Research Institute Chengdu 610041China

The hybrid cascaded high-voltage direct current(HVDC)transmission system has various operation modes,and some operation modes have sharply increasing requirements for protection rapidity,while the traditional pilot differential protection(PDP)has poor rapidity,and even refuses to operate when faults occur on the DC ***,a novel pilot protection scheme based on traveling wave characteristics is ***,the adaptability of the traditional PDP applied in engineering is analyzed for different operation ***,the expressions of the forward traveling wave(FTW)and backward traveling wave(BTW)on the rectifier side and the inverter side are derived for different fault *** the theoretical derivation,the difference between the BTW and FTW on the rectifier side is less than zero,and the same is true on the inverter ***,in the event of an external fault of DC line,the difference between the BTW and FTW at nearfault terminal protection installation point is greater than ***,by summing over the product of the difference between BTW and FTW of the rectifier side and that of the inverter side,the fault identification criterion is *** simulation results show that the proposed pilot protection scheme can quickly and reliably identify the short-circuit faults of DC line in different operation modes.

关键词： Hybrid cascaded high-voltage direct current(HVDC)transmission system DC line operation mode pilot protection

The influences of perforating phase and bedding planes on the fracture deflection in laminated shale

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Petroleum Science 2024年第2期21卷 1221-1230页

作者： Ming-Zhe Gu Mao sheng Xiao-Ying Zhuang Xin-Yi li Gen-sheng li National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China College of Petroleum Engineering China University of PetroleumBeijing102249China College of Civil Engineering Tongji UniversityShanghai200092China

The perforating phase leads to complex and diverse hydraulic fracture propagation behaviors in laminated shale formations. In this paper, a 2D high-speed imaging scheme which can capture the interaction between perforating phase and natural shale bedding planes was proposed. The phase field method was used to simulate the same conditions as in the experiment for verification and hydraulic fracture propagation mechanism under the competition of perforating phase and bedding planes was *** results indicate that the bedding planes appear to be no influence on fracture propagation while the perforating phase is perpendicular to the bedding planes, and the fracture propagates along the perforating phase without deflection. When the perforating phase algins with the bedding planes, the fracture initiation pressure reserves the lowest value, and no deflection occurs during fracture propagation. When the perforating phase is the angle 45°, 60°and 75°of bedding planes, the bedding planes begin to play a key role on the fracture deflection. The maximum deflection degree is reached at the perforating phase of75°. Numerical simulation provides evidence that the existence of shale bedding planes is not exactly equivalent to anisotropy for fracture propagation and the difference of mechanical properties between different shale layers is the fundamental reason for fracture deflection. The findings help to understand the intrinsic characteristics of shale and provide a theoretical basis for the optimization design of field perforation parameters.

关键词： Shale Propagation Perforating Bedding Structure

Perception of fundamental science to boost lithium metal anodes toward practical application

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Green Energy & Environment 2024年第3期9卷 454-472页

作者： Jinkun Wang li Wang Hong Xu li sheng Xiangming He Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084China

As a key material for lithium metal batteries(LMBs),lithium metal is one of the most promising anode materials to break the bottleneck of battery energy density and a commonly used active material for reference *** lithium anodes are regarded as the holy grail of lithium batteries,decades of exploration have not led to the successful commercialization of LMBs,due mainly to the challenges related to the inherent properties of lithium *** pave the way for further investigation,herein,a comprehensive review focusing on the fundamental science of lithium are ***,the natures of lithium atoms and their isotopes,lithium clusters and lithium crystals are revisited,especially their structural and energetic ***,the electrochemical properties of lithium metal are *** important concepts and scientific questions,including the electronic structure of lithium,influence of high pressure and low temperature on the properties of lithium,factors influencing lithium deposition,generation of lithium dendrites,and electrode potential of lithium in different electrolytes,are explained and analyzed in *** to improve the performance of lithium anodes and thoughtfulness about the electrode potential in lithium battery research are proposed.

关键词： lithium Cluster Crystal Physicochemical property Fundamental science

New formula for predicting the plastic buckling pressure of steel torispherical heads under internal pressure

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第8期25卷 618-630页

作者： sheng YE Keming li Jinyang ZHENG Shan SUN Institute of Process Equipment Zhejiang UniversityHangzhou 310027China Engineering Research Center for High Pressure Process Equipment and Safety of Ministry of Education Hangzhou 310027China State Key Laboratory of Fluid Power and Mechatronic Systems Hangzhou 310058China

Thin-walled torispherical heads under internal pressure can fail by plastic buckling because of compressive circumferential stresses in the head ***,existing formulas still have limitations,such as complicated expressions and low accuracy,in determining buckling *** this paper,we propose a new formula for calculating the buckling pressure of torispherical heads based on elastic-plastic analysis and experimental ***,a finite element(FE)method based on the arc-length method is established to calculate the plastic buckling pressure of torispherical heads,considering the effects of material strain hardening and geometrical *** buckling pressure results calculated by the FE method in this paper have good consistency with those of BOSOR5,which is a program for calculating the elastic-plastic bifurcation buckling pressure based on the finite difference energy ***,the effects of geometric parameters,material parameters,and restraint form of head edge on buckling pressure are ***,a new formula for calculating plastic buckling pressure is developed by fitting the curve of FE results and introducing a reduction factor determined from experimental ***,based on the experimental results,we compare the predictions of the new formula with those of existing *** is shown that the new formula has a higher accuracy than the existing ones.

关键词： Torispherical head Plastic buckling Elastic-plastic analysis Prediction formula Finite element method

Novel high-safety aeroengine performance predictive control method based on adaptive tracking weight

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Chinese Journal of Aeronautics 2024年第7期37卷 352-374页

作者： Qian CHEN Hanlin sheng Jie ZHANG Jiacheng li College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Increasing attention has been attracted to the dynamic performance and safety of advanced performance predictive control systems of the next-generation *** latest research demonstrates that Subspace-based Improved Model Predictive Control(SIMPC)can overcome the difficulty in solving the predictive model in MPC/NMPC ***,applying constant design parameters cannot maintain consistent control effects in all ***,the designed system relies too much on sensor-measured data,and thus it is difficult to thoroughly validate the safety of the system because of its high *** means that any potential hardware/software faults will endanger the ***,this paper first presents a novel nonlinear mapping relationship to adaptively tune the tracking weight online with the change of Power Lever Angle(PLA)and real-time relative tracking ***,without introducing additional design parameters,an Adaptive Tracking Weight-based SIMPC(ATW-SIMPC)controller is designed to improve the control performance in all operating states ***,a Primary/Backup Hybrid Control(PBHC)strategy with the ATW-SIMPC controller as the primary system and the traditional speed(Nf)controller as the backup system is proposed to ensure *** designed affiliated switching controller and the real-time monitor therein can be used to realize reasonable and smooth switching between primary/backup systems,so as to avoid bump *** PBHC system switches to the Nf controller when the ATW-SIMPC controller is wrong because of potential hardware/software faults;otherwise,the ATW-SIMPC controller keeps acting on the *** main results prove that the ATW-SIMPC controller with the optimal nonlinear mapping relationship,compared with the existing SIMPC controller,uplifts the dynamic control performance by 32%and reduces overshoots to an allowable limit,resulting in a better control effect in full *** comparison results consistently i

关键词： Aeroengine Model predictive control Hybrid system Adaptive weight Safety

Recent advances in promising drugs for primary prevention of gastroesophageal variceal bleeding with cirrhotic portal hypertension

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 4-13页

作者： Ji-Yao sheng Zi-Fan Meng Qiao li Yong-sheng Yang Department of Hepatobiliary and Pancreatic Surgery the Second Hospital of Jilin UniversityChangchun 130041China Jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases the Second Hospital of Jilin UniversityChangchun 130041China

Background:Gastroesophageal variceal bleeding is one of the most severe complications of patients with *** primary prevention drugs,including non-selectiveβ-blockers,have effectively reduced the incidence of bleeding,their efficacy is limited due to side effects and related *** recent advances in precision medicine,precise drug treatment provides better treatment *** sources:literature search was conducted in PubMed,MEDliNE and Web of Science for relevant articles published up to May *** on clinical trials was obtained from https://***/and http://***/.Results:The in-depth understanding of the pathogenesis and advances of portal hypertension has enabled the discovery of multiple molecular targets for promising *** to the site of action,these drugs could be classified into four classes:intrahepatic,extrahepatic,both intrahepatic and extrahepatic targets and *** these classes of drugs offer advantages over traditional treatments in prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal ***:This review classified and summarized the promising drugs,which prevent gastroesophageal variceal bleeding by targeting specific markers of pathogenesis of portal hypertension,demonstrating the significance of using the precision medicine strategy to discover and develop promising drugs for the primary prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.

关键词： Cirrhotic portal hypertension Target drug Primary prevention Bleeding