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Chemical Research in Chinese Universities 2009年第4期25卷 579-584页

作者： chen dan-mei DONG Yan-ming SHEN Bing-xing YANG Xue-hui LI Yan-jie HU Xiao-lan Department of Materials Science and Engineering Xiamen University Xiamen 361005 P. R. China College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P. R. China

A series of bowlic cyclotriveratrylenes（CTV） with peripheral groups with different lengths were *** compounds were investigated by diferential scanning calorimetry and hot stage coupled polarizing *** CTV derivatives show thermotropic liquid crystalline *** experimental results of their thermotropic liquid crystalline behavior indicate that the clear points,the entropy changes of melting points,the crystallization temperatures,and their entropy changes all exhibited an evident odd-even effect except the melting points,which decreased monotonously with the increase of the length of the alkoxy *** parameter values of CTVs with even number carbon atoms were larger than those of CTVs with odd *** the length of alkoxyl chains was even longer,a monotonous decrease ***,in the case of the entropy changes of both melting points and crystallization temperatures,the effect was valid for all the six species,and therefore,the whole curves presented as a zig-zag form.

关键词： Cyclotriveratryleues(CTV) Bowlic liquid crystal Thermotropic liquid crystal Odd-even effect

The First Five Years of a Phase Theory for Complex Systems and Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1728-1743页

作者： dan Wang Wei chen Li Qiu Division of Decision and Control Systems KTH Royal Institute of TechnologyStockholm 10044Sweden Department of Mechanics and Engineering Science&the State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing 100871China Hong Kong University of Science and Technology Hong KongChinaand also with the Southern University of Science and TechnologyShenzhen 518055China

In this paper,we review the development of a phase theory for systems and networks in its first five years,represented by a trilogy:Matrix phases and their properties;The MIMO LTI system phase response,its physical interpretations,the small phase theorem,and the sectored real lemma;The synchronization of a multi-agent network using phase *** the end,we also summarize a list of ongoing research on the phase theory and speculate what will happen in the next five years.

关键词： Consensus and synchronization matrix phases multi-agent systems phase theory sectored real lemma small phase theorem.

Difluoromethyl phenoxathiinium salt: A new general and versatile difluoromethylating reagent with divergent ·CF_(2)H, CF_(2)H^(+), and :CF_(2) reactivities

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Science China Chemistry 2024年第3期67卷 953-962页

作者： Yuan-Qing Gu Hong-Xin Long dan-dan Zhang mei-Feng Ruan Guo-Kai Liu School of Pharmacy Shenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China

Development of practical and versatile electrophilic difluoromethylating reagent is still a grand challenge so far due to its inherent instability or low ***,we report the design and synthesis of difluoromethyl phenoxathiinium tetrafluoroborate(PT-CF_(2)H^(+)BF_(4)^(-)) as a novel difluoromethylating reagent,which proves to be a bench-stable,general,powerful and versatile reagent with divergent·CF_(2)H,CF_(2)H^(+),and:CF_(2) *** use of this reagent,we demonstrated a vast array of difluoromethyl radical transfer reactions via diverse pathways involving photocatalyst-free visible-light induction,visible-light photoredox catalysis and visible-light mediation single electron transfer of EDA ***,the green and highly effective CF_(2)H^(+) and:CF_(2) transfer reactions were also readily accomplished.

关键词： difluoromethyl phenoxathiinium salt versatile difluoromethylating reagent difluoromethyl radical difluoromthyl cation difluorocarbene

Effects of the properties of Mg(OH)_(2)precursor on the hydrothermal synthesis of magnesium oxysulfate whiskers

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Particuology 2024年第9期92卷 13-23页

作者： Thanayos Boonrit mei Yang Guangwen chen Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian116023China University of Chinese Academy of Sciences Beijing100049China

Magnesium oxysulfate(MOS)whiskers are commonly synthesized through a dissolution-precipitation mechanism,wherein Mg(OH)_(2)dissolves to form Mg(OH)64−,followed by reactions with SO_(4)^(2−)and H_(2)O to yield MOS ***,the impact of Mg(OH)_(2)precursor properties on the formation process of MOS whiskers has been insufficiently explored,and sector-like and needle-like morphologies were both observed in previous *** this study,we systematically investigated how the properties of Mg(OH)_(2)precursors influenced the crystalline structure and morphology of MOS *** various experimental conditions,MgSO_(4)·5Mg(OH)_(2)·2H_(2)O(152MOS)whiskers were consistently obtained,regardless of Mg(OH)_(2)morphology and *** size of Mg(OH)_(2)emerged as a critical factor in shaping the morphology of 152MOS ***-sized Mg(OH)_(2)(≤106±37 nm)favored the formation of sector-like whiskers,while larger-sized Mg(OH)_(2)(≥206±98 nm)encouraged the development of needle-like *** distinction was attributed to the slower dissolution rate exhibited by larger-sized Mg(OH)_(2),maintaining a smaller number of 152MOS nuclei and promoting the growth of needle-like whiskers instead of the aggregation of 152MOS nuclei into sector-like *** addition,the effects of the molar ratio of Mg^(2+)to SO_(4)^(2−)and hydrothermal temperature were also *** average length and diameter of the needle-like whiskers prepared with Mg(OH)_(2)of 331±145 nm under optimized conditions were 77±32 and 0.39±0.10μm,*** study presented an effective strategy for controlling the morphology of 152MOS whiskers.

关键词： Magnesium oxysulfate whiskers Morphology control Precursor Microreactor

On the Factors Influencing the High Stretch-Flangeability of a Low-Density 1180 MPa Fe-Mn-Al-C-Nbδ-QP Steel

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1291-1300页

作者： dan‑dan Cui Peng chen Peng‑Fei Wang Xiao‑Wu Li Department of Materials Physics and Chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

Low-densityδ-quenching and partitioning(δ-QP)steels with excellent strength and ductility have been recently ***,there are still rare reports on the formability of δ-QP steels,which are critical for satisfying the manufacture of structural parts during the application in automotive *** the present work,an 1180 MPa Fe–Mn–Al–C–Nbδ-QP steel with a high ductility was adopted for the stretch–flangeability ***δ-QP steel was developed by separated quenching and partitioning processes.A good hole expansion ratio(HER)of 34.9±0.9%was obtained in the quenched steel,but it has been further increased to 52.2%by the tempering *** improved stretch–flangeability was attributed to the enhanced austenite stability and deformation *** the one hand,the stability of austenite was increased by carbon partitioning during tempering,which reduced crack possibility via the suppression of the fresh martensite *** the other hand,the tempering treatment released the internal stress caused by martensitic transformation and reduced the difference in strength among different phases,resulting in an increase in the resistance to crack initiation and propagation.

关键词： Hole expansion ratio Low-densityδ-quenching and partitioning(δ-QP)steel Stretch-flangeability Austenite stability Deformation uniformity

STING signaling in islet macrophages impairs insulin secretion in obesity

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Science China(Life Sciences) 2024年第2期67卷 345-359页

作者： Ze Hong Saihua chen Jing Sun dan cheng Hanli Guo Jiahao mei Xiang Zhang Munire Maimaiti Haiping Hao Peng Cao Haiyang Hu chen Wang School of Pharmacy Nanjing University of Chinese MedicineNanjing 210023China State Key Laboratory of Natural Medicines Department of Life Science and TechnologyChina Pharmaceutical UniversityNanjing 211198China School of Life Sciences Westlake UniversityHangzhou 310012China

The innate immune regulator stimulator of interferon genes(STING)mediates self-DNA sensing and leads to the induction of type I interferons and inflammatory cytokines,which promotes the progression of various inflammatory and autoimmune *** immune system plays a critical role in regulating obesity-induced islet dysfunction,whereas the potential effect of STING signaling is not fully ***,we demonstrate that STING is mainly expressed and activated in islet macrophages upon high-fat diet(HFD)***^(-/-)alleviates HFD-induced islet inflammation by inhibiting the expression of pro-inflammatory cytokines and the infiltration of ***,palmitic acid incubation promotes mitochondrial DNA leakage into the cytosol and subsequently activates STING pathway in ***,STING activation in macrophages impairs glucose-stimulated insulin secretion by mediating the engulfment ofβcell insulin secretory *** inhibiting STING activation enhances insulin secretion to control ***,our results reveal a regulatory mechanism in controlling the islet inflammation and insulin secretion in dietinduced obesity and suggest that selective blocking of the STING activation may be a promising strategy for treating type 2 diabetes.

关键词： STING obesity type 2 diabetes insulin macrophages islet

Risk Constrained Self-scheduling of AA-CAES Facilities in Electricity and Heat Markets:A Distributionally Robust Optimization Approach

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1159-1167页

作者： Zhiao Li Laijun chen Wei Wei Shengwei mei Department of Electrical Engineering Tsinghua UniversityBeijing 100084China New Energy(Photovoltaic)Industry Research Center Qinghai UniversityXining 810016China IEEE

Advanced adiabatic compressed air energy storage(AA-CAES)has the advantages of large capacity,long service time,combined heat and power generation(CHP),and does not consume fossil fuels,making it a promising storage technology in a low-carbon *** appropriate self-scheduling model can guarantee AA-CAES’s profit and attract ***,very few studies refer to the cogeneration ability of AA-CAES,which enables the possibility to trade in the electricity and heat markets at the same *** this paper,we propose a multimarket self-scheduling model to make full use of heat produced in *** volatile market price is modeled by a set of inexact distributions based on historical data through-***,the self-scheduling model is cast as a robust risk constrained program by introducing Stackelberg game theory,and equivalently reformulated as a mixed-integer linear program(MILP).The numerical simulation results validate the proposed method and demonstrate that participating in multienergy markets increases overall *** impact of uncertainty parameters is also discussed in the sensibility analysis.

关键词： Advanced adiabatic compressed air energy storage(AA-CAES) conditional value at risk(CVaR) distributionally robust optimization(DRO) heat market self-scheduling Stackelberg game

Application of a microscopic optical potential of chiral effective field theory in (p, d) transfer reactions

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Nuclear Science and Techniques 2024年第1期35卷 134-144页

作者： Yi-Ping Xu Si-Lu chen dan-Yang Pang School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China School of Physics Beihang UniversityBeijing 100191China

The microscopic global nucleon–nucleus optical model potential(OMP)proposed by Whitehead,Lim,and Holt,the WLH potential(Whitehead et al.,Phys Rev Lett 127:182502,2021),which was constructed in the framework of many-body per-turbation theory with state-of-the-art nuclear interactions from chiral effective field theory(EFT),was tested with(p,d)transfer reactions calculated using adiabatic wave *** target nuclei included both stable and unstable nuclei,and the incident energies reached 200 *** results were compared with experimental data and predictions using the phenomenological global optical potential of Koning and Delaroche,the KD02 ***,we found that the micro-scopic WLH potential described the(p,d)reaction angular distributions similarly to the phenomenological KD02 potential;however,the former was slightly better than the latter for radioactive *** average,the obtained spectroscopic factors(SFs)using both microscopic and phenomenological potentials were similar when the incident energies were below approxi-mately 120 ***,their difference tended to increase at higher incident energies,which was particularly apparent for the doubly magic target nucleus 40Ca.

关键词： Microscopic optical model potential (p,d)transfer Spectroscopic factors

Dynamic coverage of mobile multi-target in sensor networks based on virtual force

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The Journal of China Universities of Posts and Telecommunications 2024年第4期31卷 83-94页

作者： Huang Qingdong Wang mei chen chen Han Zhuang School of Communication and Information Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

A distributed self-control coverage method for mobile multi-target based on virtual force(MMTVF)is proposed to monitor dynamic targets using a mobile sensor network(MSN).The dynamic coverage method is introduced to maintain network connectivity and optimize the coverage of moving *** method consists of two parts,one is the virtual force model which is proposed for motion control,and the other is the whale optimization algorithm which is improved to optimize node positions and achieve a steady state *** virtual resultant force stretches the network towards uncovered targets using its multi-target attractive force,maintains network connectivity during network stretching using its attractive force,and prevents node collisions while nodes are moving using its repulsive *** operating mechanism of the multi-target attractive force and other forces is thoroughly *** criteria for the model in different application scenarios are also *** comparisons demonstrate MMTVF has significant advantages over other similar approaches.

关键词： mobile sensor network(MSN) dynamic coverage virtual force moving targets

Fiducial Approach for the Storage Reliability Assessment of Complex Repairable Systems

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Journal of Systems Science & Complexity 2024年第4期37卷 1653-1671页

作者： YANG Yang ZHAO Letian chen Siyi YU dan University of Chinese Academy of Sciences Beijing 100190China Computer Application Institute of Nuclear Industry Beijing 100142China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

In recent years,there has been a growing focus on high-reliability products in industrial and military *** plays a crucial role in these products,and as a result,research on storage reliability has gained more *** paper specifically targets a class of products with complex structures that require long-term storage,regular testing,and ***,an expression method for system availability is provided based on the reliability structure of the system and the maintenance situation of the constituent equipment in *** the expression of system availability is typically complex and difficult to compute,and the storage life of the system cannot be represented as an explicit function of the reliability indicators of the constituent equipment,it is challenging to evaluate the availability and storage life of repairable *** address this,the paper proposes a comprehensive evaluation methodology for assessing the storage reliability of complex repairable systems based on fiducial *** approach is employed to derive point estimates and determine the lower fiducial limits for both system availability and storage ***,simulation results demonstrate that this comprehensive evaluation method for storage reliability of complex repairable systems is not only convenient but also highly effective.

关键词： Availability fiducial method repairable system storage life