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Facile synthesis of hypercrosslinked resin via photochlorination of p-xylene and succedent alkylation polymerization

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Chinese Chemical Letters 2011年第9期22卷 1115-1118页

作者： ling ling Bai Yong Hao Zhou Xiu li Wang Si Guo Yuan xian li wu School of Chemical Engineering and Energy Zhengzhou University Zhengzhou 450001 China

A combination of photochlorination ofp-xylene and succedent Friedel-Crafts alkylation polymerization was firstly used in the preparation of the hypercrosslinked adsorptive resin. The data of GC-MS and GC showed that a series of chlorizates were produced when p-xylene was photochlorinated. Hypercrosslinked resins could be synthesized by copolymerization, self-polymerization of chlorizates or post crosslinking reaction. The chemical structure and micromorphology of the porous resins were characterized by BET, FF-IR, SEM and elementary analysis （EA）. The results showed that the novel adsorptive resins possess high BET surface near to 1038 m^2/g and large pore volumes range from 0.5 to 1.2 cm^3/g.

关键词： Hypercrosslinked resin Synthesis p-Xylene Photochlorination Polymerization

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The microRNA miR-184 regulates the CYP303A1 transcript level to control molting of Locusta migratoria

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Insect Science 2021年第4期28卷 941-951页

作者： Yan-li Wang li-xian wu Hui-Yong li Xue-Qin Wen En-Bo Ma Kun-Yan Zhu Jian-Zhen Zhang Research Institute of Applied Biology Shanxi UniversityTaiyuanShanxiChina College of life Science Shanxi UniversityTaiyuanShanxiChina Department of Entomology Kansas State UniversityManhattanKSUSA

Cytochrome P450 monooxygenases(CYPs)play essential physiological functions in ***303A1 is highly conserved in insect species studied to date,and shows an indispensable role for adult eclosion in both Locusta migratoria and Drosophila ***,how CYP303A1 is regulated to control insect developmental processes remains *** this study,we discovered functional binding sites for miR-184 in the coding sequence of *** luciferase reporter assay showed that miR-184 could target LmCYP303A1 and regulate its expression in ***,overexpression of miR-184 through microinjection of agomir to locusts reduced the transcripts of LmCYP303A1 and led to abnormal molting,which is similar to the phenotype of silencing LmCYP303A1 by direct injection of dsLmCYP303A1 to ***,down-regulation of miR-184 by injection of antagomir increased the LmCYP303A1 transcript and caused molting *** findings suggested that miR-184 could target LmCYP303A1 to regulate the molting process in ***,which might be considered as a novel target for pest control.

关键词： CYP303A1 gene regulation insect molting Locusta migratoria miR-184

Delving into high-quality SVBRDF acquisition: A new setup and method

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Computational Visual Media 2024年第3期10卷 523-541页

作者： Chuhua xian Jiaxin li Hao wu Zisen lin Guiqing li School of Computer Science and Engineering South China University of TechnologyGuangzhou 510006China Guangdong Shidi Intelligence Technology Ltd.Guangzhou 510000China

In this study, we present a new andinnovative framework for acquiring high-qualitySVBRDF maps. Our approach addresses the limitations of the current methods and proposes a newsolution. The core of our method is a simple hardwaresetup consisting of a consumer-level camera, LEDlights, and a carefully designed network that canaccurately obtain the high-quality SVBRDF propertiesof a nearly planar object. By capturing a ﬂexiblenumber of images of an object, our network usesdifferent subnetworks to train different property mapsand employs appropriate loss functions for each ofthem. To further enhance the quality of the maps, weimproved the network structure by adding a novel skipconnection that connects the encoder and decoder withglobal features. Through extensive experimentation usingboth synthetic and real-world materials, our resultsdemonstrate that our method outperforms previousmethods and produces superior results. Furthermore,our proposed setup can also be used to acquire physicallybased rendering maps of special materials.

关键词： acquisition setup SVBRDF acquisition material capture global skip connection

Heteroepitaxial growth of Au@Pd core–shell nanocrystals with intrinsic chiral surfaces for enantiomeric recognition

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Rare Metals 2024年第1期43卷 225-235页

作者： Feng-Xia wu Feng-Hua li Xia-li Lv Qi-xian Zhang Guo-Bao Xu Wen-Xin Niu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Shaoxing Institute of Technology Shanghai UniversityShaoxing 312000China University of Science and Technology of China Hefei 230026China School of Materials Science and Engineering Shanghai UniversityShanghai 200436China Zhejiang Institute of Advanced Materials Shanghai UniversityJiashan 314113China University of Chinese Academy of Sciences Beijing 100039China

Noble metal surfaces with intrinsic chirality serve as an ideal candidate for investigating enantioselective chemistry due to their superior chemical durability and high catalytic ***,significant advance has been made in synthesizing metal nanocrystals with intrinsic ***,the majority reports are limited to ***,through a heteroepitaxial growth strategy,the synthesis of metal nanocrystals with intrinsic chirality to palladium was extended for the first time and their application in enantioselective recognition was *** heteroepitaxial growth strategy allows for transferring the chirality of homochiral Au nanocrystals to Au@Pd core–shell *** employing the chiral Au@Pd nanocrystals as enantiomeric recognizing elements,a series of electrochemical sensors for chiral discrimination were *** optimal conditions,the peak potential between D-dihydroxyphenylalanine(D-DOPA)and L-dihydroxyphenylalanine(L-DOPA)is about 80 m V,and the peak current of D-DOPA is 2 times as much as that of L-DOPA,which enables the determination of the enantiomeric excess(EE,%)of ***,this report not only introduces a heteroepitaxial growth strategy to synthesize metal nanocrystals with intrinsic chirality,but also demonstrates the superior capability of integrating intrinsic chirality and catalytic properties into metal nanocrystals for chiral recognition.

关键词： Core–shell nanostructures Chirality transfer Electrochemical sensors Chiral recognition Chiroplasmonics

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Cytoplasmic FKBPs are involved in molting and metamorphosis through regulating the nuclear localization of EcR

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Insect Science 2024年第3期31卷 759-772页

作者： xian Zhang Qiao-Ran Wang Qian wu Jun Gu li-Hua Huang Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology School of Life SciencesSouth China Normal UniversityGuangzhouChina Guangmeiyuan R&D Center Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied TechnologySouth China Normal UniversityMeizhouChina

Molting and metamorphosis are important physiological processes in insects that are tightly controlled by ecdysone receptor(EcR)through the 20-hydroxyecdysone(20E)signaling *** is a steroid nuclear receptor(SR).Several FK506-binding proteins(FKBPs)have been identified from the mammal SR complex,and are thought to be involved in the subcellular trafficking of ***,their roles in insects are poorly *** explore whether FKBPs are involved in insect molting or metamorphosis,we injected an FKBP inhibitor(FK506)into a lepidopteran insect,Spodoptera litura,and found that molting was inhibited in 61.11%of the larvae,and that the time for larvae to pupate was significantly extended.A total of 10 FKBP genes were identified from the genome of *** and were clustered into 2 distinct groups,according to their subcellular localization,with FKBP13 and FKBP14 belonging to the endoplasmic reticulum(ER)group and with the other members belonging to the cytoplasmic(Cy)*** the CyFKBPs were significantly upregulated in the prepupal or pupal stages,with the opposite being observed for the ER group ***506 completely blocked the transfer of EcR to the nucleus under 20E induction,and significantly downregulated the transcriptional expression of many 20E signaling genes.A similar phenomenon was observed after RNA interference of2 CyFKBPs(FKBP45 and FKBP12b),but not for *** together,our data indicate that the cytoplasmic FKBPs,especially FKBP45 and FKBP12b,mediate the nuclear localization of EcR,thereby regulating the 20E signaling and ultimately affecting molting and metamorphosis in insects.

关键词： EcR FKBP metamorphosis molting RNAi subcellular localization

Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu Yang li Yu liu Xiao-Xiao ling li-Guang wu li Yang Lan Yang Bo Yang Yong-Gang Zhao xian-Hua li State Key Laboratory of lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

Microstructure and water-swelling mechanism of red-bed mudstone in the Xining region,Northeastern Tibetan Plateau

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2537-2551页

作者： Huan Guan Yong Ren Sixiang ling Xiyong wu Tao Yu xian li Sen Wang Chunwei Sun School of Civil Engineering Southwest Jiaotong UniversityChengdu610031China Faculty of Geosciences and Engineering Southwest Jiaotong UniversityChengdu611756China Moe Key Laboratory of High-speed Railway Engineering Southwest Jiaotong UniversityChengdu610031China Guangzhou Metro Design and Research Institute Co Ltd. Guangzhou510010China Chengdu City Construction Investment Group Co Ltd. Chengdu610036China

This paper examines the effect of the microstructure and electrical conductivity(EC)on the swelling ratio and pressure in red-bed mudstone sampled from arid areas in the Xining region in the northeastern Tibetan Plateau.A series of laboratory tests,including swelling experiments,X-ray diffraction(XRD),and scanning electron microscope(SEM),was carried out for mechanical and microstructural *** coupled influence of the EC and microstructural parameters on the expansion ratio and pressure was investigated,and the weight coefficients were discussed by the entropy weight *** results revealed an increasing exponential trend in EC,and the maximum swelling speed occurred at an EC of approximately 10 μS/*** addition,a method for predicting the expansion potential is proposed based on the microstructure,and its reliability is verified by comparing with swelling experimental *** addition,according to the image analysis results,the ranges of the change in the clay minerals content(CMC),the fractal dimension(FD),the average diameter(AD)of pores,and the plane porosity(PP)are 23.75%-53%,1.08-1.17,7.53-22.45 mm,and 0.62%-1.25%,***,mudstone swelling is negatively correlated with the plane porosity,fractal dimension and average diameter and is linearly correlated with the clay mineral ***,the weight values prove that the microstructural characteristics,including FD,AD,and PP,are the main factors influencing the expansion properties of red-bed mudstones in the Xining *** on the combination of macro and micro-analyses,a quantitative analysis of the swelling process of mudstones can provide a better reference for understanding the mechanism of expansion behavior.

关键词： Mudstones Microstructure Swelling characteristics Electrical conductivity(EC) Scanning electron microscope Water-swelling

Theoretical Design of Defects as a Driving Force for Ion Transport in li3OBr Solid Electrolyte

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Energy & Environmental Materials 2024年第3期7卷 147-157页

作者： Xingyun Luo Yanlu li xian Zhao State Key Lab of Crystal Materials and Institute of Crystal Materials Shandong University Center for Optics Research and Engineering Shandong University

Due to ever-increasing concerns about safety issues in using li ionic batteries,solid electrolytes have extensively *** li-rich antiperovskite li3OBr has been considered as a promising solid electrolyte candidate,but it still suffers challenges to achieve a high ionic conductivity owing to the high intrinsic symmetry of the crystal ***,we presented a design strategy that introduces various point defects and grain boundaries to break the high lattice symmetry of li3OBr crystal,and their effect and microscopic mechanism of promoting the migration of li-ion were explored *** has been found that liiare the dominant defects responsible for the fast li-ion diffusion in bulk li3OBr and its surface,but they are easily trapped by the grain boundaries,leading to the annihilating of the Frenkel defect pair V'li+li,and thus limits the V'lidiffusion at the grain *** VBrdefect near the grain boundaries can effectively drive V'liacross the grain boundary,thereby converting the carrier of li+migration from li,in the bulk and surface to V'liat the grain boundary,and thus improving the ionic conductivity in the whole li3OBr *** work provides a comprehensive insight into the li+transport and conduction mechanism in the li3OBr *** opens a new way of improving the conductivity for all-solid-state li electrolyte material through the defect design.

关键词： defects density functional theory ionic migration solid electrolyte

Evaluation of transmission risk of respiratory particles under different ventilation strategies in an elevator

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Building Simulation 2024年第5期17卷 771-784页

作者： liangyu Zhu xian li Bujin Feng Fan liu School of Civil Engineering and Architecture Linyi UniversityLinyi276000China College of Agriculture Shandong Agricultural UniversityTaian271018China School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai200093China

People in elevators are at risk of respiratory infection because the elevator cabin is crowded and has poor *** exhaled particles may be inhaled by the susceptible person,deposited on the surface and suspended in the elevator,which can result in direct and indirect ***,whether the air vent designs adopted in the elevator can effectively reduce the transmission risk of respiratory particles remains *** this study,the dispersion of particles under four common ventilation strategies used in the commercial elevator was investigated by proven computational fluid dynamics(CFD)*** flow field was simulated with the RNG κ-ξ turbulence model and the Lagrangian method was adopted to track particle *** effects of air vent layout and airflow rate on particle transmission were *** found that more than 50% of exhaled particles(average value)were suspended in the cabin and difficult to discharge under the investigated ventilation *** deposited fraction of particles on the susceptible person reached up to 39.14% for infiltration ventilation,which led to a high risk of contact *** the ventilation rate could not significantly reduce the inhalation proportion of particles due to the poor airflow distribution inside the elevator.A more proper ventilation strategy should be explored for the elevator to control transmission risk.

关键词： particle dispersion transmission risk elevator ventilation strategy computational fluid dynamics(CFD)