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Enhanced Sensing Mechanism Based on Shifting an Exceptional Point

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Research 2024年第3期6卷 285-292页

作者： Xuan Mao Guo-Qing Qin Hao Zhang bo-Yang Wang Dan long Gui-Qin Li Gui-Lu long Department of Physics State Key Laboratory of Low-Dimensional Quantum PhysicsTsinghua UniversityBeijing 100084China Beijing Institute of Radio Measurement The Second Academy of China Aerospace Science and Industry Corporation(CASIC)Beijing 100854China Purple Mountain Laboratories Nanjing 21111China Frontier Science Center for Quantum Information Beijing 100084China Beijing Academy of Quantum Information Sciences Beijing 100193China

Non-Hermitian systems associated with exceptional points (EPs) are expected to demonstrate a giant response enhancement for various sensors. The widely investigated enhancement mechanism based on diverging from an EP should destroy the EP and further limits its applications for multiple sensing scenarios in a time sequence. To break the above limit, here, we proposed a new enhanced sensing mechanism based on shifting an EP. Different from the mechanism of diverging from an EP, our scheme is an EP nondemolition and the giant enhancement of response is acquired by a slight shift of the EP along the parameter axis induced by perturbation. The new sensing mechanism can promise the most effective response enhancement for all sensors in the case of multiple sensing in a time sequence. To verify our sensing mechanism, we construct a mass sensor and a gyroscope with concrete physical implementations. Our work will deepen the understanding of EP-based sensing and inspire designing various high-sensitivity sensors in different physical systems.

关键词： mechanism shifting exceptional

Effect of spinal cord extracts after spinal cord injury on proliferation of rat embryonic neural stem cells and Notch signal pathway in vitro

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Asian Pacific Journal of Tropical Medicine 2014年第7期7卷 562-567页

作者： Qing-Zhong Zhou Ge Zhang Hai-bo long Fei Lei Fei Ye Xu-Feng Jia Yun-long Zhou Jian-Ping Kang Da-Xiong Feng Department of Spine Surgery Affiliated Hospital of Luzhou Medical College Department of Spine Surgery Popele's Hospital of Luzhou Department of Spine Surgery Affiliated TCM Hospital of Luzhou Medical College

Objective:To investigate the effect of the spinal cord extracts(SCE)after spinal cord injuries(SCIs)on the proliferation of rat embryonic neural stem cells(NSCs)and the expressions of mRNA of Notch1 as well as of Hes1 in this process in ***:The experiment was conducted in 4 different mediums:NSCs+PBS(Group A-blank control group),NSCs+SCE with healthy SD rats(Croup B-normal control group),NSCs+SCE with SD rats receiving sham-operation treatment(Croup C-sham-operation group)and NSCs+SCE with SCIs rats(Group D-paraplegic group).Proliferative abilities of 4 different groups were analyzed by MTT chromatometry after co-culture for 1,2,3,4 and 5 d,*** expressions of Notch 1 and Hes1 mRNA were also detected with RT-PCR after co-culture for 24 and 48 h,***:After co-culture for 1,2,3,4 and 5 d respectively,the MTT values of group D were significantly higher than those of group A,group B and group C(P0.05).both the expressions of Notch1 and Hes1 mRNA of group D were significantly higher than those of other 3 groups after co-culture for 24 h and 48 h as well(P0.05).There was no difference in expressions of Notch1and Hes1 mRNA between 24 h and 48 h treatment in group ***:SCE could promote the proliferation of *** is demonstrated that the microenvironment of SCI may promote the proliferation of ***,SCE could increase the expression of Notch1 and Hes1 mRNA of *** can be concluded that the Notch signaling pathway activation is one of the mechanisms that locally injured microenvironment contributes to the proliferation of ENSC after *** process may be performed by up-regulating the expressions of Notch1 and

关键词： Neural stem cell Cell culture Spinal cord extract Notch signal pathway

Catalysis and Inhibition of Benzimidazole Units on Thermal Imidization of Poly(amic acid) via Hydrogen bonding Interactions

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Chinese Journal of Polymer Science 2015年第4期33卷 621-632页

作者： Hui-na Wang Ming-xi Yang long-bo Luo Jie-yang Huang Ke Li Xu Wang Yan Feng 刘向阳 State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan University

The effect of benzimidazole units on thermal imidizaiton was studied when they were introduced into the main chain of poly（amic acid）（PAA）. The thermal imidization process of PAA-PABZ synthesized by 3,3＇,4,4＇- biphenyltetracarboxylic dianhydride （BPDA） and 2-（4-aminophenyl）-5（6）-aminobenzimidazole （PABZ） was studied by TGA, DSC, DMA, FTIR and in situ FTIR. The results of FTIR and in situ FTIR indicate benzimidazole units act as an ＂in situ＂ catalyst to accelerate thermal imidization of PAA to polyimide （PI） when the temperature is lower than 170℃. FTIR and ~H-NMR results demonstrate that in situ catalysis is caused by the hydrogen bonding interactions between C=N of benzimidazole and -NH- in -CONH- of PAA and the semi-ionization of the H in imidazole ring of benzimidazole. However, when the imidization temperature is higher than 170℃, the thermal imidization process is inhibited. DMA and in situ FTIR results illustrate that the decreased mobility of PI-PABZ macromolecular chains and the reduced reactive ability of anhydride formed during the intramolecular breakdown of polymer chains lead to the inhibition of thermal imidization process.

关键词： Benzimidazole Hydrogen bonding Catalysis Inhibition Polyimide.

Influence of Steric Hindrance Between Hydrogen Atoms of Linkage Groups and Adjacent Phenyls on Properties of Polyimide

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Chemical Research in Chinese Universities 2012年第5期28卷 926-930页

作者： PANG Yu-wei LUO long-bo CHEN Yi ZHANG Peng WANG Xu PENG Chao-rong LIU Xiang-yang State key Laboratory of Polymer Material and Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065P.R.China Sichuan Institute of Atomic Energy Chengdu 610066P.R.China

A diamine monomer 4,4′-methylenedianiline（MDA） was introduced to modify the polyimide of pyromellitic dianhydride（PMDA） and 4,4′-oxydianiline（ODA） by polycondensation. A series of polyamic acids was synthesized from MDA and ODA of different molar ratios with PMDA of sum mole of moles of MDA and ODA, and polyimide films were obtained by thermal imidization. Polyimide（PI） films were characterized by tensile testing, dynamic mechanical analysis（DMA）, thermal gravimetry analysis（TGA）, Fourier transform infrared spectroscopy （FTIR）, wide X-ray diffraction（WAXD） and molecular simulation. With the increase of MDA content, the tensile strength and thermal decomposition temperature remained generally stable compared with those of PMDA/ODA polyimide. Unexpectedly, the glass transition temperature（Tg） and Young＇s modulus increased from 388.7 °C and 2.37 GPa to 408.3 °C and 5.74 GPa, respectively. The results of WAXD and molecular simulation indicate the steric hindrance among hydrogen atoms of the linkage groups and adjacent phenyls enhanced the properties of the polyimide modified with MDA.

关键词： Polyimide Modification Glass transition temperature Steric hindrance

Theoretical Studies on the Kinetics and Mechanisms of Reactions for Methyl Vinyl Ether and Ozone

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Chinese Journal of Chemical Physics 2008年第4期21卷 324-332页

作者： bo long Ming-qiang Huang Zhen-ya Wang Wei-jun Zhang Laboratory of Environment Spectroscopy Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences. Hefei 230031 China School of Physics and Information Science Guizhou University for Nationalities Guiyang 550025 China

The interconversion between the two distinct isomers of methyl vinyl ether （MVE）, the formation of the primary ozonides from O3-initated reactions of MVE, the transformation between the primary ozonides, and the subsequent fragmentation were studied using quantum chemical methods at the BHandHLYP/6311＋＋G（d,p） level of theory for optimized geometries and frequency calculations and at the QCISD/631G（d,p） level for the single point energy calculations. The rate coefficients were calculated for the temperature range 280-440 K by using the canonical transition state theory （TST）. For ozone addition to MVE, there are two different possibilities discussed on the basis of two different possible orientations for ozone attack. The results of the theoretical study indicate that although the synperiplanar-MVE is 7.11 kJ/mol more stable than the antiperiplanar-MVE, the antiperiplanar-MVE plays a more important role in formation of the primary ozonides because the primary ozonides formed from the ozone addition antiperiplanar-MVE are more stable and the energy barriers corresponding to transition states are lower. The intereonversion between the primary ozonides formed from the ozone addition to antiperiplanar-MVE is the most accessible compared with the transformations between other primary ozonides. The cleavage of the primary ozonides mainly leads to the formation of the CH2OO, which is in agreement with the experimental estimates. The calculated overall rate constant for the ozone-initiated reactions is 4.8× 10^-17 cm^3/（molecule.s） at 298.15 K, which agrees with the experimental value for ethyl vinyl ether.

关键词： Methyl vinyl ether Ozone Reaction pathway Primary ozonide Interconversion Rate constant Transition state theory

Synthesis of a Novel Co-B/CTAB Catalyst via Solid-state-reaction at Room Temperature for Hydrolysis of Ammonia-borane

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Chemical Research in Chinese Universities 2020年第6期36卷 1209-1216页

作者： HU Haibin long bo JIANG Yifan SUN Shichang Ibrahim LAWAN ZHOU Weiming- ZHANG Mingxin WANG Liwei ZHANG Fan YUAN Zhanhui College of Materials Engineering Fujian Agriculture and Forestry UniversityFuzhou 350002P.R.China College of Mechanical and Electrical Engineering Fujian Agriculture and Forestry UniversityFuzhou 350002P.R.China Key Laboratory of National Forestry&Grassland Bureau for Plant Fiber Functional Materials Fujian Agriculture and Forestry UniversityFuzhou 350002P.R.China Ocean College Minjiang UniversityFuzhou 350108P.R.China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240P.R.China

Cobalt-boride(Co-B)is emerging as one of the promising materials in the base-hydrolytic dehydrogena-tion of ammonia-borane(AB).In order to avoid the low specific area and poor catalytic capacity of Co-B catalyst caused by aggregation arising from the strong reducing property and rapid reaction condensation of sodium borohy-dride(NaBHa),novel cobalt boride/cetyltrimethylammonium bromide(Co-B/CTAB)catalyst was obtained via solid-state grinding at room temperature,and the catalyst was further characterized by XRD,SEM,XPS and *** hydrogen generation rate(HGR)was then determined by the hydrolysis reaction of *** SEM images indicate that a lot of irregular folds and curled edges are formed on the sample with a maximum surface area of 145.57 m2/g,thus possibly resulting in the high hydrogen production(HGR was 10.68 ***),which may be attributed to CTAB that provide favorable large specific surface area and abundant porous ***,catalyst will not be affected by solvants during solid-state *** a diluent,the surfactant CTAB hindered the reaction rate of sodium borohydride reduction to cobalt boride and obtained the novel catalyst with a large specific surface area.

关键词： Hydrogen generation rate Ammonia borane Co-B Solid-state reaction

Neural dynamics for improving optimiser in deep learning with noise considered

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CAAI Transactions on Intelligence Technology 2024年第3期9卷 722-737页

作者： Dan Su Predrag S.Stanimirović Ling bo Han long Jin School of Information Science and Engineering Lanzhou UniversityLanzhouChina Faculty of Sciences and Mathematics University of NišNišSerbia School of Electronics and Information Engineering Guangdong Ocean UniversityZhanjiangChina

As deep learning evolves,neural network structures become increasingly sophisticated,bringing a series of new optimisation *** example,deep neural networks(DNNs)are vulnerable to a variety of *** neural networks under privacy constraints is a method to alleviate privacy leakage,and one way to do this is to add noise to the ***,the existing optimisers suffer from weak convergence in the presence of increased noise during training,which leads to a low robustness of the *** stabilise and improve the convergence of DNNs,the authors propose a neural dynamics(ND)optimiser,which is inspired by the zeroing neural dynamics originated from zeroing neural *** authors first analyse the relationship be-tween DNNs and control ***,the authors construct the ND optimiser to update network ***,the proposed ND optimiser alleviates the non-convergence problem that may be suffered by adding noise to the gradient from different ***,experiments are conducted on different neural network structures,including ResNet18,ResNet34,Inception-v3,MobileNet,and long and short-term memory *** results using CIFAR,YouTube Faces,and R8 datasets demonstrate that the ND optimiser improves the accuracy and stability of DNNs under noise-free and noise-polluted *** source code is publicly available at https://***/longJin-lab/ND.

关键词： deep learning deep neural networks

Study on the Intermediate in the o-Phenylenediamine Oxidative Reaction Using Hemoglobin as A Mimetic Peroxidase in Aqueous-Organic Two Phase

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Wuhan University Journal of Natural Sciences 2002年第1期7卷 117-121页

作者： Li Hai-cheng Li De-jia Huang bo Jin De-long Zou Guo-lin College of Life Sciences Wuhan University Wuhan 430072 Hubei China

Hemoglobin was used as a mimetic enzyme for peroxidase to catalyze the oxidative reaction of o-phenylenediamine with H2O2 which functioned as an oxidant. The relationship between physicochemical properties of the intermediate and enzymatic activity of hemoglobin was studied. Since the solubility of the intermediate in the reaction is higher in butanol phase than in water phase, the intermediate itself diffused from the aqueous phase to the butanol phase. The experimental results showed that the rate of product and the stability of intermediate were associated with the temperature and the pH value of the buffer. The formation rate of intermediate and half-life period reveal the maximal in pH7, nevertheless, the whole rate of the catalytic reaction is the greatest in pH5, which the ratio of the initial rate in final product formation compared to that intermediate formation is the greatest.

关键词： hemoglobin mimetic enzyme intermediate two phase reaction mechanism

Glutamicibacter nicotianae AT6:A new strain for the efficient biodegradation of tilmicosin

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Journal of Environmental Sciences 2024年第8期142卷 182-192页

作者： Huijuan Li Hao Zhou Liling Fan long Meng Yanyun Zhao Lanmei Zhao bo Wang College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdao 266590China College of Chemistry and Chemical Engineering Heze UniversityHeze 274015China College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China

The degradation of tilmicosin(TLM),a semi-synthetic 16-membered macrolide antibiotic,has been receiving increasing ***,there are three tilmicosin degradation methods,and among them microbial degradation is considered the best due to its high efficiency,eco-friendliness,and low ***,we found a new strain,Glutamicibacter nicotianae ***6,capable of degrading high-concentration TLM at 100 mg/L with a 97%removal *** role of tryptone was as well investigated,and the results revealed that the loading of tryptone had a significant influence on TLM *** toxicity assessment indicated that strain AT6 could efficiently convert TLM into less-toxic *** on the identified intermediates,the degradation of TLM by AT6 processing through two distinct pathways was then proposed.

关键词： Tilmicosin Glutamicibacter nicotianae Biodegradation Degradation pathway Pharmaceutical wastewater