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Synthesis and Biological Activity of Novel Spin Labeled Derivatives of 4′-Demethyl-4-deoxypodophyllotoxin

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Chemical Research in Chinese Universities 2010年第5期26卷 753-756页

作者： XU Jing SUN Xiao-hua zhang jia-qiang zhang Zhi-wei TIAN Xuan State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 P. R. China

Seven novel spin labeled derivatives of 4＇-demethyl-4-deoxypodophyllotoxin with nitroxyl radi- cals（TMHPO and TMPRO） were prepared and their cytotoxic and antioxidative activities were tested. Their cytotoxic activities were tested against two tumor cell lines（A-549 and HL-60） in vitro. Among them, five compounds show higher inhibition activity against A-549 cells compared with the clinical drug VP-16（2） and parent compound 4＇-demethyl-4-deoxypodophyllotoxin（DDPT, 6）. Compounds 8, 10 and 13 show excellent inhibition activity against HL-60 cells. Furthermore, the antioxidative activities of them were tested. All the seven spin labeled compounds show stronger antioxidative activity compared with VP-16（2） and DDPT（6）. The partition coefficients P of these derivatives were determined.

关键词： 4'-Demethyl-4-deoxypodophyllotoxin Nitroxyl radical Antiturnor activity Antioxidative activity

Density-Functional Theories for Polyelectrolyte Systems

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Chinese Journal of Polymer Science 2024年第9期42卷 1302-1312,I0006页

作者： jia-Wei zhang Yu-Hang zhang Bao-Hui Li qiang Wang School of Physics Nankai UniversityTianjin90001China Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Polymer density-functional theories(PDFTs)have distinct advantages in the study of polyelectrolyte(PE)systems over experiments and molecular *** we give an introductory review of some PDFTs recently developed for PE *** start with a general formalism of PDFTs and its relation to the widely used polymer self-consistent field theory(SCFT),then explain the various correlations that are neglected in SCFT but can be accounted for in PDFTs,including those due to the excluded-volume interaction and chain connectivity of uncharged polymers,the electrostatic correlations of small ions,and the chain correlations in *** also list some applications of PDFTs for PE systems,and finally give some perspectives on future *** hope that our review can attract more researchers to apply and further develop PDFTs as a promising class of theoretical and computational tools.

关键词： Polymer density-functional theories Polyelectrolytes Correlations

Neuroendocrine,epigenetic,and intergenerational effects of general anesthetics

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World Journal of Psychiatry 2020年第5期10卷 81-94页

作者： Anatoly E Martynyuk Ling-Sha Ju Timothy E Morey jia-qiang zhang Department of Anesthesiology and the McKnight Brain Institute University of Florida College of MedicineGainesvilleFL 32610United States Department of Anesthesiology University of Florida College of MedicineGainesvilleFL 32610United States Department of Anesthesiology and Perioperative Medicine Henan Provincial People’s HospitalPeople's Hospital of Zhengzhou UniversityZhengzhou 450003Henan ProvinceChina

The progress of modern medicine would be impossible without the use of general anesthetics(GAs).Despite advancements in refining anesthesia approaches,the effects of GAs are not fully reversible upon GA *** deficiencies attributed to GA exposure may persist in neonates or endure for weeks to years in the *** studies on the mechanisms of the long-term adverse effects of GAs are needed to improve the safety of general anesthesia but they are hampered not only by ethical limitations specific to human research,but also by a lack of specific biological markers that can be used in human studies to safely and objectively study such *** latter can primarily be attributed to an insufficient understanding of the full range of the biological effects induced by GAs and the molecular mechanisms mediating such effects even in rodents,which are far more extensively studied than any other *** most recent experimental findings in rodents suggest that GAs may adversely affect many more people than is currently ***,we have shown that anesthesia with the commonly used GA sevoflurane induces in exposed animals not only neuroendocrine abnormalities(somatic effects),but also epigenetic reprogramming of germ cells(germ cell effects).The latter may pass the neurobehavioral effects of parental sevoflurane exposure to the offspring,who may be affected even at levels of anesthesia that are not harmful to the exposed *** large number of patients who require general anesthesia,the even larger number of their future unexposed offspring whose health may be affected,and a growing number of neurodevelopmental disorders of unknown etiology underscore the translational importance of investigating the intergenerational effects of *** this mini review,we discuss emerging experimental findings on neuroendocrine,epigenetic,and intergenerational effects of GAs.

关键词： Brain General anesthetic Sevoflurane Corticosterone Cortisol Histone acetylation Deoxyribonucleic acid methylation Intergenerational effects Gamma aminobutyric acid

Zeolites for the separation of ethylene,ethane,and ethyne

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 137-146页

作者： Binyu Wang qiang Li Haoyang zhang jia-Nan zhang Qinhe Pan Wenfu Yan State Key Laboratory of Inorganic Synthesis&Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China Key Laboratory of Advanced Energy Catalytic and Functional Materials Preparation College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450012China Key Laboratory of Advanced Materials of Tropical Island Resources(Ministry of Education) School of Chemistry and Chemical EngineeringHainan UniversityHaikou 570228China

The cost-effective separation of ethylene(C_(2)H_(4)),ethyne(C_(2)H_(2)),and ethane(C_(2)H_(6))poses a significant challenge in the contemporary chemical *** contrast to the energy-intensive high-pressure cryogenic distillation process,zeolite-based adsorptive separation offers a low-energy *** review provides a concise overview of recent advancements in the adsorptive separation of C_(2)H_(4),C_(2)H_(2),and C_(2)H_(6)using zeolites or zeolite-based *** commences with an examination of the industrial significance of these compounds and the associated separation ***,it systematically examines the utilization of various types of zeolites with diverse cationic species in such separation *** then it explores how different zeolitic structures impact adsorption and separation capabilities,considering principles such as cation-πinteraction,π-complexation,and steric separation concerning C_(2)H_(4),C_(2)H_(2),and C_(2)H_(6)***,it discusses methods to enhance the separation performance of zeolites and zeolite-based adsorbents,encompassing structural design,modifications,and ion exchange ***,it summarizes current research trends and future directions,highlighting the potential application value of zeolitic materials in the field of C_(2)H_(4),C_(2)H_(2),and C_(2)H_(6)separation and offering recommendations for further investigation.

关键词： zeolite ethylene ethane cation-πinteraction π-complexation

Enhanced preparation of dendritic metallic vanadium in recyclable NaCl-KCl-VCl_(2) molten salt by V_(2)CO electrolysis

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Rare Metals 2024年第8期43卷 3961-3973页

作者： jia-Liang An Ming-Yong Wang Yong-Zheng jia Jin-Tao zhang Bao-Yan Feng Shu-qiang jiao State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China College of Material Science and Engineering Hebei Province Laboratory of Inorganic Nonmetallic MaterialsNorth China University of Science and TechnologyTangshan 063210China

A promising method for the preparation of pure metallic vanadium via V_(2)CO anode electrolysis was proposed and *** simple and controllable synthesis of a molten chloride salt containing VCl_(2) by an insitu reaction between VCl_(3) and metallic vanadium was verified through thermodynamic analysis and ***-KCl-VCl_(2) molten salt exhibited excellent recycling performance and could be repetitively used to prepare metallic vanadium by V_(2)CO *** V^(2+) ions remained in the molten salt after *** electrolysis conditions,such as the cathode diameter,current density,V^(2+) ion concentration,and temperature,were optimised to maximise the current *** was also simulated to reveal the regulatory *** highest current efficiency was 85%.The purity of metallic vanadium was up to 99.8%.In this study,an easy and efficient preparation of pure metallic vanadium was achieved.

关键词： V_(2)CO Metallic vanadium Current efficiency Molten salt electrolysis

Electromagnetic wave absorption performance and rheological behavior of rubber composites with low mass filling rate carbon nanofiber aerogel

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Journal of Materiomics 2024年第4期10卷 928-936页

作者： Zhiyi zhang Bicheng Zhou Lan jia Wenwen Yu qiang Zheng College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan030000China rd Research Institute of China Electronics Technology Group Corporation Taiyuan030032China Department of Polymer Science&Engineering Zhejiang UniversityHangzhou310027China

With the development of electronic information science and technology,electromagnetic information security and electromagnetic pollution become more and more *** wave absorption(EMWA)rubber based on the absorbent of carbon with low density and good corrosion resistance is a kind of good EMWA materials for solving electromagnetic information security and electromagnetic *** this article,three-dimensional network structure carbon nanofiber aerogels(3DNSCAs)are prepared by vacuum annealing of three-dimensional network structure agarose/zinc acetate obtained by freeze-drying of agarose/zinc acetate *** EMWA rubber composites with 2.2%(in mass)3DNSCAs have almost the same density as silicone rubber(PDMS),and the dispersity of 3DNSCAs in PDMS is studied by rheological *** effective absorption bandwidth(EAB,frequency for reflection loss<–10 dB)of the 2 mm thick PDMS/C-800 is 4 GHz,and the minimum value of reflection loss(RL_(min))is−52 dB with the thickness of 3.5 *** PDMS/C-1000 with the thickness of 3.5 mm has an EAB up to 4.8 *** cross section(RCS)reduction of PDMS/C-800 can achieve 20 dB⋅m2 at the frequency of 6 GHz.

关键词： Electromagnetic wave absorption Rubber composite Carbon aerogel Rheological behavior Power loss density

Molecular Ferroelastic Induced by Mono-/Double-Protonation Strategy

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Chinese Journal of Chemistry 2024年第15期42卷 1706-1712页

作者： jia-Qi Luo Meng-Meng Lun qiang-qiang jia Zhi-Jie Wang Hai-Feng Lu Yi zhang Da-Wei Fu Institute for Science and Applications of Molecular Ferroelectrics Key Laboratory of the Ministry of Education for Advanced Catalysis MaterialsZhejiang Normal UniversityJinhuaZhejiang 321004China Ordered Matter Science Research Center Jiangsu Key Laboratory for Science and Applications of Molecular FerroelectricsSoutheast UniversityNanjingJiangsu 211189China

Molecular ferroelastics with the natural features of mechanical flexibility and switchable spontaneous strain have attracted widespread attention in the scientific community due to their potential applications in tunable gratings,flexible memorizers,strain sensors,and intelligent ***,most designs of molecular ferroelastics remain in the stage of blind exploration,posing a challenge to achieve a functional ferroelastic more ***,we have successfully obtained a molecular ferroelastic,[Me_(2)NH(CH_(2))_(2)NH_(3)](ReO_(4))_(2)(Me_(2)NH(CH_(2))_(2)NH_(3)=N,N-dimethylethylenediammonium),under the guidance of the mono-/double-protonation ***_double-protonated[Me_(2)NH(CH_(2))_(2)NH_(3)](ReO_(4))_(2) undergoes a paraelastic-ferroelastic phase transition with the Aizu notation of 2/mFi at 322 ***,the theoretical calculation and experimental measurement simultaneously show that[Me_(2)NH(CH_(2))_(2)NH_(3)](ReO_(4))_(2) possesses good mechanical flexibility,because its elastic modulus(E)of 8.26 GPa and hardness(H)of 0.45 GPa are smaller than the average values of organic crystals(E of 12.05 GPa and H of 0.5 GPa),which makes it promising to apply in wearable pressure sensors,implantable medical sensors,high-precision tuners,*** work further enriches the molecular ferroelastic family and demonstrates that mono-/double-protonation is one of the effective molecular modification strategies for designing ferroelastics.

关键词： Molecular crystal Ferroelastic Mono-/double-protonation Mechanical flexibility Phase transition Crystal engineering Computational chemistry Molecular dynamics

Neonatal Propofol and Etomidate Exposure Enhance Inhibitory Synaptic Transmission in Hippocampal Cornus Ammonis 1 Pyramidal Neurons

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Chinese Medical Journal 2016年第22期129卷 2714-2724页

作者： jia-qiang zhang Wan-Ying Xu Chang-Qing Xu Department of Anesthesiology University of Florida College of Medicine Gainesville FL 32611 USA Department of Anesthesiology The People's Hospital of Zhengzhou University Zhengzhou Henan 450003 China Department of Neurobiology Wake Forest University Winston-Salem NC 27106 USA

Background：Propofol and etomidate are the most important intravenous general anesthetics in the current clinical use and that mediate gamma-aminobutyric acid＇s （GABAergic） synaptic ***,their long-term effects on GABAergic synaptic transmission induced by neonatal propofol or etomidate exposure remain *** investigated the long-term GABAergic neurotransmission alterations,following neonatal propofol and etomidate ***：Sprague-Dawley rat pups at postnatal days 4 6 were underwent 6-h-long propofol-induced or 5-h-long etomidate-induced *** performed whole-cell patch-clamp recording from pyramidal cells in the cornus ammonis 1 area of acute hippocampal slices of postnatal 80-90 *** and miniature inhibitory GABAergic currents （spontaneous inhibitory postsynaptic currents [sIPSCs] and miniature inhibitory postsynaptic currents [mIPSCs]） and their kinetic characters were *** glutamatergic tonic effect on inhibitory transmission and the effect of bumetanide on neonatal propofol exposure were also ***：Neonatal propofol exposure significantly increased the frequency of mIPSCs （from 1.87 ± 0.35 Hz to 3.43 ± 0.51 Hz,P 〈 0.05） and did not affect the amplitude of mIPSCs and *** propofol and etomidate slowed the decay time of mIPSCs kinetics （168.39 ± 27.91 ms and 267.02 ± 100.08 ms vs.68.18 ± 12.43 ms;P 〈 0.05）.Bumetanide significantly blocked the frequency increase and reversed the kinetic alteration of mIPSCs induced by neonatal propofol exposure （3.01 ± 0.45 Hz and 94.30 ± 32.56 ms）.Conclusions：Neonatal propofol and etomidate exposure has long-term effects on inhibitory GABAergic *** might act at pre-and post-synaptic GABA receptor A （GABAA） receptors within GABAergic synapses and impairs the glutamatergic tonic input to GABAergic synapses;etomidate might act at the postsynaptic site.

关键词： Etomidate Gamma-aminobutyric Acid Glutamate Propofol Synapse Transmission

Prevalence of sleep-disordered breathing in elderly patients with cardiac pacemaker: a case-control study

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Journal of Geriatric Cardiology 2005年第2期2卷 114-117页

作者： Haiyun WU Shiwen WANG jianping jia Wenli zhang qiang XU Institute of Geriatric Cardiology General Hospital of PLA Beijing 100853 China Institute of Geriatric Cardiology General Hospital of PLA Beijing 100853 China The 463th Hospital of Chinese PLA Shenyang 110042 China Institute of Geriatric Cardiology General Hospital of PLA Beijing 100853 China Institute of Geriatric Cardiology General Hospital of PLA Beijing 100853 China

Objective To investigate the prevalence of sleep-disordered breathing in elderly patients with permanent cardiac pacemaker implantation due to bradyarrhythmias, and the relationship between pacing mode and patients' sleep apnea-hypopnea *** Forty-four elderly patients (＞60 years) with cardiac pacemaker and their 44 controls matched for gender, age, body mass index and cardiovascular morbidity were studied using polysomnography or portable sleep monitoring device. Results Prevalence of sleep-disordered breathing (apnea-hypopnea index ≥5/h) was 44.7% and the mean apnea-hypopnea index was 8.2 ±4.1/h in the cardiac pacemaker group, which were significantly higher than those in control subjects (25% and 4.6±2.4/h, respectively, P＜0.01 and P＜0.05). The mean apnea-hypopnea index of patients with DDD or AAI pacemaker was significantly lower than that of patients with VVI pacemaker. Conclusions Sleep-disordered breathing was more common in patients who had their cardiac pacemaker implanted due to bradyarrhythmias than in their matched controls. Compared with VVI pacing, DDD or AAI pacing may be more beneficial to patients with bradyarrhythmias and sleep-disordered breathing.

关键词： sleep-disordered breathing bradyarrhythmia cardiac pacing case-control study