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Macroscopic Regulation of Hierarchical Nanostructures in Liquid-crystalline Block Copolymers towards Functional Materials

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Chinese Journal of Polymer Science 2021年第4期39卷 397-416,I0004页

作者： feng cai Yu-Xuan Chen Wen-Zhong Wang Hai-feng Yu Department of Materials Science and Engineering and Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of EngineeringPeking UniversityBeijing 100871China

The great potential of liquid-crystalline block copolymers(LCBCs)containing photoresponsive mesogens toward novel applications in photonics and nanotechnology has been attracting increasing attention,due to the combination of the inherent property of microphase separation of block copolymers and the hierarchically-assembled structures of liquid-crystalline polymers(LCPs).The periodically ordered nanostructures in bulk film of LCBCs can be acquired by supramolecular cooperative motion,derived from the interaction between liquid-crystalline elastic deformation and microphase separation,which are able to improve physical properties of polymer film toward advanced functional ***,various micro/nano-patterned structures have been fabricated via light manipulation of photoresponsive LCBCs with good reproducibility and mass *** to recent developments in synthesis and polymerization techniques,diverse azobenzene-containing LCBCs have been designed,resulting in the creation of a wide variety of novel *** review illustrates recent progresses in macroscopic regulation of hierarchical nanostructures in LCBCs towards functional *** existing challenges are also discussed,showing perspectives for future studies.

关键词： Liquid-crystalline block copolymers Microphase separation Hierarchical nanostructures Functional materials

Monocyte to High-density Lipoprotein Cholesterol Ratio as a Predictor of Nonalcoholic Fatty Liver Disease in Childhood Obesity

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Current Medical Science 2024年第4期44卷 692-697页

作者： Jun-feng ZHANG feng-qing cai Xiu-cai ZHANG Qing YE Department of Laboratory Medicine Children’s HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhou310052China

Objective Inflammation is involved in the development and progression of nonalcoholic fatty liver disease(NAFLD).The monocyte to high-density lipoprotein cholesterol ratio(MHR)has emerged as a marker for various inflammation-related *** aim of the present study was to investigate the association between the MHR and NAFLD in a population with childhood *** Based on hepatic ultrasound,a total of 504 children with obesity(357 with NAFLD and 147 without NAFLD)were included in the *** correlation between the MHR and NAFLD risk factors was assessed by Pearson’s and Spearman’s *** stepwise logistic regression analyses were conducted to explore the association between the MHR and the risk of *** The MHR in patients with NAFLD was significantly greater than that in patients without NAFLD[0.52(0.44-0.67)versus 0.44(0.34-0.57),P<0.001].Multivariate stepwise logistic regression analysis demonstrated that the MHR[odds ratio(OR):1.033,95%confidence interval(CI):1.015-1.051;P<0.001]was an independent predictor of NAFLD in childhood obesity patients,as were age(OR:1.205,95%CI:1.059-1.371;P=0.005],waist circumference[OR:1.037,95%CI:1.008-1.067;P=0.012],and alanine transaminase[OR:1.067,95%CI:1.045-1.089;P<0.001].Additionally,MHR quartiles showed a significant positive association with the incidence of NAFLD after adjusting for potential confounding *** The present study showed that the MHR may serve as an available and useful indicator of NAFLD in individuals with childhood obesity.

关键词： nonalcoholic fatty liver disease obesity monocyte-to-high-density lipoprotein ratio marker

Study on carbon emission in prefecture-level cities of china

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High Technology Letters 2012年第1期18卷 101-106页

作者： feng Ying cai Bofeng Institute of Scientific and Technical Information of China Beijing 100038 P.R. China College of Environmental Sciences and Engineering Peking University Beijing 100871 P.R. China Center for Climate and Environmental Policy Chinese Academy for Environmental Planning Beijing 100012 P.R. China

The study on greenhouse gas inventory in urban China lags far behind the global level. The important factor that curbs the carbon inventory of cities of China is inventory methodology and scope. Given the insufficiency of Chinese cities carbon inventory, a system and accounting model （scopel＋ scope2） as well as principles and boundaries were proposed for China. The carbon emissions in scopel and scopel＋ scope2 were calculated in Chinese prefecture-level cities. The EDGAR dataset was used for the calculation of scopel carbon emissions in cities in China and the level of uncertainty was analyzed as well. The results showed that the direct carbon emission of cities in China was about 31.65% of China total emissions. The scopel＋ scope2 carbon emissions in cities of China were calculated based on the GIS and RS model. The results showed that the sum of direct （scopel） and indirect （scope2） carbon emissions of cities in China accounted for 38.80% of total China carbon emissions.

关键词： cities carbon emission inventory scope

On the Quasi-Concavity of Equipment Sharing Games with Perishable Raw Materials

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Journal of Systems Science and Systems Engineering 2021年第6期30卷 649-666页

作者： Jun Li Xiaoqiang cai Yinlian Zeng Hairong feng School of Economics and Management Southwest Jiaotong UniversityChengdu 610031China Shenzhen Research Institute of Big Data Shenzhen 518172China School of Data Science The Chinese University of Hong KongShenzhenShenzhen 518172China School of Business Southern University of Science and TechnologyShenzhen 518055China School of Business Sichuan Normal UniversityChengdu 610101China

We study the equipment sharing problem where a group of food&beverage companies share the same equipment of a contractor and wish to have their processing tasks coordinated such that the total cost is *** raw materials to be processed are perishable,which incur a decay cost as time *** key issue of this equipment sharing problem is how to allocate the total cost among the *** apply cooperative game theory to tackle this issue and formulate the problem as an equipment sharing ***,we study the 1-equipment sharing game in which all participants share one *** show that the 1-equipment sharing game is quasi-concave when the fixed operation cost is larger than a certain *** then discuss the special case where the processing time for all participants is *** this case,we further investigate the properties of the 1-equipment sharing game and the multi-equipment sharing *** identify the conditions under which the Shapely value and the T-value can be easily calculated for the 1-equipment and multi-equipment sharing games.

关键词： Equipment sharing quasi-concave games perishable raw materials decay loss

Dual fermion condensate and phase transition in QED_3

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Science China(Physics,Mechanics & Astronomy) 2013年第6期56卷 1116-1119页

作者： feng HongTao YIN PeiLin SUN WeiMin zong HongShi Department of Physics Southeast University Department of Physics Nanjing University Joint Center for Particle Nuclear Physics and Cosmology

In this paper,we investigate the behaviors of dual fermion condensate in QED 3 under variation of *** means of Dyson-Schwinger equation for the fermion propagator,we extract the dual fermion condensate and compare its behavior with the ordinary chiral fermion condensate and the chiral *** is found that the dual fermion condensate cannot be regarded as the order parameter for the confinement-deconfinement phase transition in QED ***,the change of the dual fermion condensate around the chiral phase transition point observed in the present work must therefore be interpreted as solely induced by the chiral transition.

关键词： QED 3 dual fermion condensate deconfinement phase transition chiral phase transition

Spatio-temporal evolution of ecologically-sustainable land use in China's Loess Plateau and detection of its influencing factors

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Journal of Mountain Science 2019年第5期16卷 1065-1074页

作者： QU Lu-lu LIU Yan-sui CHEN zong-feng Faculty of Geographical Science Beijing Normal University Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

Ecological land(Eco-land) is a basic resource for human beings to survive, and eco-land use is a strategy, a way to manage the land resource. So, ecologically-sustainable land use is essential for human beings to survive. This paper investigates the spatiotemporal characteristics and mechanisms of urban-rural eco-land using a new and innovative integration way based on eco-land change data in China's Loess Plateau(LP) prefecture level cities and explores factors of eco-land change. The spatial difference characteristic of eco-land among different level cities in the LP is that: small cities > big cities > middle cities. From 2009 to 2016, the eco-land in the LP from the perspective of urban-rural areas has changed significantly. Significant differences of urban-rural eco-land were identified among various urban growth types, and all the cities in the LP were further classified into four types based on eco-land change trend, with type A and B cities identified as the vital zone and major zone. Taking the eco-fragile region Loess Plateau(LP) as an example, our results demonstrated that the migrants to cities in LP could relieve ecological pressures and promote restoration of ecological vegetation. We have demonstrated that urbanization and the influence of government policy can be discerned through the quantification of the spatial-temporal change of eco-land and suggest that combining both urban and rural eco-land can support more effective land use decisions and provide theoretical basis for the practical application of urban planning, policy-making and sustainable development. What's more, governments should strive to population mobility and restore vegetation to sustain this fragile ecological environment.

关键词： Ecologically-sustainable land use Spatio-temporal evolution influencing factor Population migration Loess Plateau

Effects of short-term osmotic stress on leaf hydraulic conductivity and ZmPIPs mRNA accumulation in maize seedlings

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Journal of Integrative Agriculture 2016年第11期15卷 2497-2506页

作者： WANG Wei-feng zong Yu-zheng ZHANG Sui-qi State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau/Institute of Soil and Water Conservation Northwest A & F University College of Forestry Shanxi Agricultural University College of Agriculture Shanxi Agricultural University

Plants maintain water balance by varying hydraulic properties, and plasma membrane intrinsic proteins（PIPs） may be involved in this process. Leaf xylem and root hydraulic conductivity and the m RNA contents of four highly expressed Zm PIP genes（Zm PIP1;1, Zm PIP1;2, Zm PIP2;2, and Zm PIP2;5） in maize（Zea mays） seedlings were investigated. Under well-watered conditions, leaf hydraulic conductivity（K_（leaf）） varied diurnally and was correlated with whole-plant hydraulic conductivity. Similar diurnal rhythms of leaf transpiration rate（E）, K_（leaf） and root hydraulic conductivity（K_（root）） in well-watered plants are important for maintaining whole-plant water balance. After 2 h of osmotic stress treatment induced by 10% polyethylene glycol 6000, the K_（root） of stressed plants decreased but K_（leaf） increased, compared with well-watered plants. The m RNA contents of four Zm PIPs were significantly up-regulated in the leaves of stressed plants, especially for Zm PIP1;2. Meanwhile, Zm PIP2;5 was significantly down-regulated in the roots of stressed plants. After 4 h of osmotic stress treatment, the E and leaf xylem water potentials of stressed plants unexpectedly increased. The increase in K_（leaf） and a partial recovery of K_（root） may have contributed to this process. The m RNA content of Zm PIP1;2 but not of the other three genes was up-regulated in roots at this time. In summary, the m RNA contents of these four Zm PIPs associated with K_（leaf） and K_（root） change in maize seedlings during short-term osmotic stress, especially for Zm PIP1;2 and Zm PIP2;5, which may help to further reveal the hydraulic resistance adjustment role of Zm PIPs.

关键词： maize short-term osmotic stress hydraulic conductivity ZmPIP

Dynamic stability and manipulation of bright matter-wave solitons by optical lattices in Bose-Einstein condensates

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Chinese Physics B 2012年第2期21卷 98-106页

作者： Song Chang-Sheng Li Jing zong feng-De Institute of Nonlinear Physics Zhejiang Normal UniversityJinhua 321004China

An extended variation approach to describing the dynamic evolution of self-attractive Bose-Einstein condensates is developed. We consider bright matter-wave solitons in the presence of a parabolic magnetic potential and a timespace periodic optical lattice. The dynamics of condensates is shown to be well approximated by four coupled nonlinear differential equations. A noteworthy feature is that the extended variation approach gives a critical strength ratio to support multiple stable lattice sites for the condensate. We further examine the existence of the solitons and their stabilities at the multiple stable lattice sites. In this case, the analytical predictions of Bose-Einstein condensates variational dynamics are found to be in good agreement with numerical simulations. We then find a stable region for successful manipulating matter-wave solitons without collapse, which are dragged from an initial stationary to a prescribed position by a moving periodic optical lattice.

关键词： Bose-Einstein condensates Gross-Pitaevskii equation matter-wave solitons controlled manipulation

Characteristics and implications of stress state in a gold mine in Ludong area, China

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1363-1372页

作者： Peng Li Mei-feng cai Qi-feng Guo Sheng-jun Miao School of Civil and Resource Engineering University of Science and Technology Beijing Key Laboratory of High-Efficient Mining and Safety of Metal Mines (Ministry of Education of China) University of Science and Technology Beijing Beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology Beijing

In this study, we obtained information from twenty-one measurement points on the stress magnitudes and orientations of a gold mine in the Ludong area. We used the overcoring technique with an improved hollow inclusion strain gauge and then analyzed the distribution characteristics of the in situ stress field. The results indicate that the stress field is characterized by σH > σh > σv and σH > σv > σh(where σH, σh, and σv are the maximum horizontal, minimum horizontal, and vertical principal stresses, respectively). The regional stress field is dominated by horizontal principal stress. The σH, σh, and σv values show a gradual increasing trend with depth. The σH is predominantly oriented in the NWW–SEE or near-EW direction. We also confirmed the correspondence between the measured stress field and the regional geological structure. In addition, based on the measured stress data, we discuss the implications of the in situ stress with respect to fault activity in the mine area.

关键词： in situ stress measurement improved hollow inclusion strain gauge stress field geological structure fault activity