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Measuring relic abundance of minimal dark matter at hadron colliders

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Science China(Physics,Mechanics & Astronomy) 2019年第8期62卷 55-74页

作者： qinghong Cao Ti Gong KePan Xie Zhen Zhang Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Collaborative Innovation Center of Quantum Matter Center for High Energy Physics Peking University Center for Theoretical Physics Department of Physics and Astronomy Seoul National University

We consider the special case that the dark matter(DM) candidate is not detected in direct-detection programs when the experimental sensitivity reaches the neutrino flux background. In such circumstance the DM searches at the colliders impose constraints on the DM relic abundance if the DM candidate is a WIMPs type. Specifically, we consider the triplet(quintet and septet) DMs in the framework of minimal DM model and explore the potential of discovering the DM candidate in the mono-jet, mono-photon and vector boson fusion channels at the Large Hadron Collider(LHC) and future 100 TeV hadron collider. If the DM candidate in such a scenario is discovered at the LHC, then additional DM candidates are needed to explain the observed relic *** the other hand, null results in those DM searching programs at the colliders give rise to lower limits of DM relic abundance.

关键词： dark matter electro weak interactions hadron colliders

Geological emission of methane from the Yakela condensed oil/gas field in Talimu Basin, Xinjiang, China

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Journal of Environmental Sciences 2008年第9期20卷 1055-1062页

作者： Tang Junhong Bao Zhengyu Xiang Wu Gou qinghong China Univ Geosci Minist Educ Key Lab Biogeol & Environm Geol Wuhan 430074 Peoples R China Hangzhou Dianzi Univ Dept Environm Engn & Sci Hangzhou 310018 Peoples R China Sun Yat Sen Univ Dept Earth Sci Guangzhou 510275 Guangdong Peoples R China

A static flux chamber method was applied to study natural emissions of methane into the atmosphere in the Yakela condensed oil/gas field in Talimu Basin, Xinjiang, China. Using an online method, which couples a gas chromatography/high-temperature conversion/isotope ratio mass spectrometry (GC/C/MS) together, the 13C/12C ratios of methane in the flux chambers were measured. The results demonstrated that methane gases were liable to migrate from deep oil/gas reservoir to the surface through microseepage and p...

关键词： the Yakela condensed oil/gas field methane emission stable carbon isotopes flux chamber

New judging model of fuzzy cluster optimal dividing based on rough sets theory

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Journal of Systems Engineering and Electronics 2007年第2期18卷 392-397页

作者： Wang Yun Liu qinghong Mu Yong Shi Kaiquan School of Mathematics and System Sciences Shandong Univ. Jinan 250100 P. R. China School of Science Univ. of Jinan Jinan 250022 P. R. China

To investigate the judging problem of optimal dividing matrix among several fuzzy dividing matrices in fuzzy dividing space, correspondingly, which is determined by the various choices of cluster samples in the totality sample space, two algorithms are proposed on the basis of the data analysis method in rough sets theory： information system discrete algorithm （algorithm 1） and samples representatives judging algorithm （algorithm 2）. On the principle of the farthest distance, algorithm 1 transforms continuous data into discrete form which could be transacted by rough sets theory. Taking the approximate precision as a criterion, algorithm 2 chooses the sample space with a good representative. Hence, the clustering sample set in inducing and computing optimal dividing matrix can be achieved. Several theorems are proposed to provide strict theoretic foundations for the execution of the algorithm model. An applied example based on the new algorithm model is given, whose result verifies the feasibility of this new algorithm model.

关键词： Rough sets theory Fuzzy optimal dividing matrix Representatives of samples Fuzzy cluster analysis Information system approximate precision.

Some Simple Groups Which are Determined by Their Orders and Degree-Patterns

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Algebra Colloquium 2024年第2期31卷 341-346页

作者： qinghong Guo Weijun Liu Genghua Fan School of Mathematics and Statistics HNP-LAMACentral South University Changsha 410083China College of General Education Guangdong University of Science and Technology DongguanGuangdong 523083China 不详

Let G be a finite group and Irr(G)the set of all irreducible complex characters of *** cd(G)be the set of all irreducible complex character degrees of G and denote byρ(G)the set of all primes which divide some character degree of *** character-prime graphΓ(G)associated to G is a simple undirected graph whose vertex set isρ(G)and there is an edge between two distinct primes p and q if and only if the product p q divides some character degree of *** show that the finite nonabelian simple groups A_(7),J_(1),J_(3),J_(4),L_(3)(3)and U_(3)(4)are uniquely determined by their degree-patterns and orders.

关键词： irreducible complex character character-prime graph finite nonabelian simple group

Suppression of Stokes heating processes and improved optomechanical cooling with frequency modulation

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Communications in Theoretical Physics 2022年第4期74卷 42-51页

作者： Yang Bao qinghong Liao Qingmin Zhao Jing Wu Department of Electronic Information Engineering Nanchang UniversityNanchang 330031China State Key Laboratory of Low-Dimensional Quantum Physics Department of PhysicsFrontier Science Center for Quantum InformationTsinghua UniversityBeijing 100084China

Ground-state cooling of mesoscopic mechanical objects is still a major challenge in the unresolved-sideband *** present a frequency modulation(FM)scheme to achieve cooling of the mechanical resonator to its ground-state in a double-cavity optomechanical system containing a mechanical *** mean phonon number is determined by numerically solving a set of differential equations derived from the quantum master *** to efficient suppression of Stokes heating processes in the presence of FM,the ground-state cooling,indicated by numerical calculations,is significantly achievable,regardless of whether in the resolved-sideband regime or the unresolved-sideband ***,by choosing parameters reasonably,the improvement of the quantum cooling limit is found to be capable of being positively correlated with the modulation *** method provides new insight into quantum manipulation and creates more possibilities for applications of quantum devices.

关键词： ground-state cooling Stokes heating processes frequency modulation unresolved sideband

Reaction coupling as a promising methodology for selective conversion of syngas into hydrocarbons beyond Fischer-Tropsch synthesis

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Science China Chemistry 2017年第11期60卷 1382-1385页

作者： Kang Cheng Jincan Kang qinghong Zhang Ye Wang State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy MaterialsNational Engineering Laboratory for Green Chemical Production of AlcoholsEthers and EstersCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Syngas （CO/H2） is a key platform that bridges various car- bon resources （including natural gas or shale gas, coal and biomass） and liquid fuels or high-value chemicals. In addi- tion to these carbon resources, syngas can also be produced from waste and CO2. From syngas, a variety of products such as hydrocarbons, which can be either liquid fuels （gasoline, diesel fuel and jet fuel） or building-block chemicals （lower olefins and aromatics）, and oxygenates （methanol and ethanol or other C2＋ oxygenates） can be obtained. The development of efficient catalysts for the conversion ofsyngas into specific target products is the core of syngas chemistry. The selectiv- ity control is the biggest challenge in syngas chemistry.

关键词：碳氢化合物合成气转化含氧化合物联作反应液体燃料高效催化剂

Interface Engineering via Ti_(3)C_(2)T_(x) MXene Electrolyte Additive toward Dendrite-Free Zinc Deposition

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Nano-Micro Letters 2021年第6期13卷 95-107页

作者： Chuang Sun Cuiping Wu Xingxing Gu Chao Wang qinghong Wang School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhouJiangsu 221116P.R.China Faculty of Engineering and Environment Northumbria UniversityNewcastle upon Tyne NE18STUK Chongqing Key Laboratory of Catalysis and New Environmental Materials College of Environment and ResourcesChongqing Technology and Business UniversityChongqing 400067P.R.China

Zinc metal batteries have been considered as a promising candidate for next-generation batteries due to their high safety and low ***,their practical applications are severely hampered by the poor cyclability that caused by the undesired dendrite growth of metallic ***,Ti_(3)C_(2)T_(x) MXene was first used as electrolyte additive to facilitate the uniform Zn deposition by controlling the nucleation and growth process of *** MXene additives can not only be absorbed on Zn foil to induce uniform initial Zn deposition via providing abundant zincophilic-O groups and subsequently participate in the formation of robust solid-electrolyte interface film,but also accelerate ion transportation by reducing the Zn^(2+) concentration gradient at the electrode/electrolyte ***,MXene-containing electrolyte realizes dendrite-free Zn plating/striping with high Coulombic efficiency(99.7%)and superior reversibility(stably up to 1180 cycles).When applied in full cell,the Zn-V_(2)O_(5)cell also delivers significantly improved cycling *** work provides a facile yet effective method for developing reversible zinc metal batteries.

关键词： Zinc metal batteries Ti_(3)C_(2)T_(x)MXene Electrolyte additive Uniform Zn deposition

Facile purification and immobilization of organophosphorus hydrolase on protein-inorganic hybrid phosphate nanosheets

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Chinese Journal of Chemical Engineering 2023年第4期56卷 119-125页

作者： Zhenfu Wang Jie Gao qinghong Shi Xiaoyan Dong Yan Sun Department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Oriented immobilization of enzymes helps to maintain their native structure and proper orientation for high-performance engineering to meet extensive biocatalysis ***,the supporting materials used for orientated immobilization are usually costly or complicated in preparation,affecting their practical *** this work,a facile purification and immobilization method was proposed for enzyme immobilization based on organic-inorganic hybrid calcium phosphate nanocrystal(Ca Ps)induced by Cu^(2+) modified bovine serum albumin(BSA-Cu).Then,the as-prepared hybrid calcium phosphate nanosheet,BSA-Cu@Ca Ps,was utilized for one-pot purification and immobilization of His-tagged organophosphorus hydrolase(OPH)by metal-affinity binding to the incorporated ***-Cu@Ca PsOPH exhibited enhanced p H stability and thermal stability compared to the free ***,BSA-Cu@Ca Ps-OPH could retain more than 75%and 56%of initial activity after reuse 5 and 10 times,*** results demonstrated that this facile strategy was promising for the effective biodegradation of organophosphorus pesticides with the immobilized enzyme.

关键词： Calcium phosphate nanocrystal(CaPs) Biomimetic mineralization Organophosphorus hydrolase(OPH) Oriented immobilization Hydrolysis Methyl parathion

Selective oxidation of methane to formaldehyde by oxygen over silica-supported iron catalysts

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Journal of Natural Gas Chemistry 2009年第3期18卷 288-294页

作者： Jieli He Yang Li Dongli An qinghong Zhang Ye Wang State Key Laboratory of Physical Chemistry of Solid Surfaces National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 Fujian China

FeOx-SiO2 catalysts prepared by a sol-gel method were studied for the selective oxidation of methane by oxygen. A single-pass formaldehyde yield of 2.0% was obtained over the FeOx-SiO2 with an iron content of 0.5 wt% at 898 K. This 0.5 wt% FeOx-SiO2 catalyst demonstrated significantly higher catalytic performances than the 0.5 wt% FeOx/SiO2 prepared by an impregnation method. The correlation between the catalytic performances and the characterizations with UV-Vis and H2-TPR suggested that the higher dispersion of iron species in the catalyst prepared by the sol-gel method was responsible for its higher catalytic activity for formaldehyde formation. The modification of the FeOx-SiO2 by phosphorus enhanced the formaldehyde selectivity, and a single-pass formaldehyde yield of 2.4% could be attained over a P-FeOx-SiO2 catalyst （P/Fe = 0.5） at 898 K. Raman spectroscopic measurements indicated the formation of FePO4 nanoclusters in this catalyst, which were more selective toward formaldehyde formation.

关键词： selective oxidation methane formaldehyde iron catalyst sol-gel method