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Design and optical performance investigation of all-sprayable ultrablack coating

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Nano Research 2023年第12期16卷 12901-12909页

作者： chen shen Huiyong Li Shuai Sun Hui Zhang Lanqin Yan Zhong Zhang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education Laboratory of Flexible Electronics Technology Department of ChemistryTsinghua UniversityBeijing 100084China CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China

Although ultrablack surfaces are urgently needed in wide applications owing to their extremely low reflectance over a broadband wavelength,obtaining simultaneously the ultrablackness and mechanical robustness by simple process technique is still a great ***,by decoupling different light extinction effects to different layers of coating,we design an ultrablack coating that is all-sprayable in whole *** coating presents low reflectance over visible–mid-infrared(VIS–MIR)wavelength(av.R≈1%in VIS),low multi-angle scattering(bidirectional reflection distribution function(BRDF)=10-2–10-3 sr-1),together with good substrate adhesion grade and self-cleaning ability,which are superior to most reported sprayable ultrablack *** light extinction effects of each layer are *** method is also applicable in other material systems.

关键词： ultrablack spray-coating carbon nanomaterials multiple scattering intermediate layer

THE GLASS TRANSITION TEMPERATURE AND MICROSTRUCTURE OF POLYURETHANE/EPOXY RESIN INTERPENETRATING POLYMER NETWORKS NANOCOMPOSITES

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Chinese Science Bulletin 2006年第3期51卷 293-298页

作者： JIA Qingming ZHENG Maosheng shen Renjie chen Hongxiang School of Material Science and Engineering Xi'an Jiaotong UniversityXi'an 710049 China

Nanocomposites with various contents of organophilic montmorillonite (oMMT) have been prepared by adding oMMT to interpenetrating poly- mer networks (IPNs) of polyurethane and epoxy resin (PU/EP) which had been prepared by a sequential polymeric technique. DSC experiment indicates a novel phenomenon that the glass transition tem- perature (Tg) of the nanocomposites increases with the oMMT content up to 3 %, then decreases with further increasing oMMT content. In order to explain this phenomenon, crosslink density, hydrogen bond- ing in the hard segments, crystallization of the nanocomposites and the exfoliation degree of oMMT in the nanocomposites have been investigated by swelling method, FT-IR, XRD, SEM and TEM, re- spectively. The results indicate that the crosslink density and the hydrogen bonding index of the nanocomposites increase, but the crystallization de- gree of the nanocomposites decreases with increas- ing oMMT content. In addition, oMMT improves the network structure of PU/EP.

关键词：聚亚安酯环氧树脂有机蒙脱石纳米复合物玻璃态转化温度微观结构互穿聚合物网络

Effect of Benzo[a]pyrene on Detoxification and the Activity of Antioxidant Enzymes of Marine Microalgae

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Journal of Ocean University of China 2016年第2期15卷 303-310页

作者： shen chen MIAO Jingjing LI Yun PAN Luqing Ministry of Education Key Laboratory of Mariculture Ocean University of China

The objective of this study was to examine the effect ofbenzo[a]pyrene （BaP） on the detoxification and antioxidant systems of two microalgae, Isochrysis zhanjiangensis and Platymonas subcordiformis. In our study, these two algae were exposed to BaP for 4 days at three different concentrations including 0.5 μg L-1 （low）, 3 μg L-1 （mid） and 18 μg L-1 （high）. The activity of detoxi- fication enzymes, ethoxyresorufin O-deethylase （EROD） and glutathione S-transferase （GST） increased in P subcordiformis in all BaP-treated groups. In 1. zhanjiangensis, the activity of these two enzymes increased at the beginning of exposure, and then de- creased in the groups treated with mid- and high BaP. The activity of antioxidant enzyme superoxide dismutase （SOD） increased in/. zhanjiangensis in all BaP-treated groups, and then decreased in high BaP-treated group, while no significant change was observed in P subcordiformis. The activity of antioxidant enzyme catalase （CAT） increased in I. zhanjiangensis and P subcordiformis in all BaP- treated groups. The content of malondialdehyde （MDA） in Isochrysis zhanjiangensis increased first, and then decreased in high BaP-treated group, while no change occurred in P. subcordiformis. These results demonstrated that BaP significantly influenced the activity of detoxifying and antioxidant enzymes in microalgae. The metabolic related enzymes （EROD, GST and CAT） may serve as sensitive biomarkers of measuring the contamination level of BaP in marine water.

关键词： benzo[a]pyrene marine microalga detoxifying enzyme antioxidant enzyme lipid peroxidation

Revisiting the origin of modern humans in China and its implications for global human evolution

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Science China Earth Sciences 2010年第12期53卷 1927-1940页

作者： GAO Xing ZHANG XiaoLing YANG DongYa shen chen WU XinZhi Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of SciencesBeijing 100044China Laboratory of Human Evolution Chinese Academy of SciencesBeijing 100044China Graduate University of Chinese Academy of Sciences Beijing 100049China Department of Archaeology Simon Fraser UniversityVancouver V5A 1S6Canada The Royal Ontario Museum Toronto M5S 2C6Canada

The debates over the origin of modern humans have long been centered on two competing theories:the "Out-of-Africa"(single-place origin) theory and the "Multi-regional Evolution" *** is an extremely important region where many ancient human fossils were collected along with numerous associated faunal remains and *** cultural remains,unearthed from different areas in the country and covering a long time span,will help clarify the *** study of cultural materials in China is expected to shed important light on biological evolutionary patterns and social and technical developments of those early humans as well as their environmental *** on the analysis of Chinese fossils and associated materials,in conjunction with some genetic studies,this paper aims at evaluating each of the two theories in order to stimulate more *** study suggests that the evolutionary model of "Continuity with Hybridization" is most relevant in reflecting the current understanding of human evolutionary history in ***,we propose that the concept of regional diversity of evolutionary models should be seriously considered to illustrate different evolutionary modes applied to different parts of the world.

关键词： origin of modern humans China human fossils molecular biology palaeolithic archaeology

Ecotoxicological effect of zinc oxide nanoparticles on soil microorganisms

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Frontiers of Environmental Science & Engineering 2015年第5期9卷 912-918页

作者： Zhaoyi shen Zhuo chen Zhen HOU Tingting LI Xiaoxia LU Laboratory for Earth Surface Processes (Ministry of Education) College of Urban and Environmental Sciences Peking University Beijing 100871 China

The widespread production and use of zinc oxide nanoparticles （ZnO-NPs） in recent years have posed potential threat to the ecosystem. This study aimed to investigate the ecotoxicological effect of ZnO-NPs on soil microorganisms using laboratory microcosm test. Respira- tion, ammonification, dehydrogenase （DH） activity, and fluorescent diacetate hydrolase （FDAH） activity were used as ecotoxicological parameters. The results showed that in the neutral soil treated with 1 mg ZnO-NPs per g soil （fresh, neutral）, ammonification was significantly inhibited during the study period of three months, but the inhibition rate decreased over increasing time. Inhibition in respira- tion was observed in the first month of the test. In various ZnO-NPs treatments （1 rag, 5 rag, and 10 mg ZnO-NPs per g soil）, DH activity and FDAH activity were inhibited during the study period of one month. For both enzyme activities, there were positive dose-response relationships between the concentration of ZnO-NPs and the inhibition rates, but the curves changed over time due to changes of ZnO-NPs toxicity. Soil type affected the toxicity of ZnO- NPs in soil. The toxicity was highest in the acid soil, followed by the neutral soil. The toxicity was relatively low in the alkaline soil. The toxicity was not accounted for by the Zn2＋ released from the ZnO-NPs. Direct interaction of ZnO-NPs with biologic targets might be one of the reasons. The adverse effect of ZnO-NPs on soil micro- organisms in neutral and acid soils is worthy of attention.

关键词： zinc oxide nanoparticles (ZnO-NPs) soilmicroorganisms respiration ammonification dehydrogen-ase (DH) activity fluorescent diacetate hydrolase (FDAH)activity

Synthesis of Tetrahydrofuran and Tetrahydropyran Derivatives Catalyzed by Tungstophosphoric Acid in Ionic Liquid

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Chinese Chemical Letters 2005年第9期16卷 1155-1157页

作者： Wen PEI Li SUN Chun Hua XIONG chen shen College of Chemical Engineering and Materials Zhejiang University of Technology Hangzhou 310014 College of Food Science Biotechnolegy and Environmental Engingeering Zhejiang Gongshang University Hangzhou 310035

Synthesis of tetrahydrofuran and tetrahydropyran derivatives catalyzed by tungstophosphoric acid （H3PW12040） were conveniently performed with high yield from the corresponding unsaturated alcohols in ionic liquid. Sufuric acid （H2SO4）, trifluoromathanesulfonic acid （TfOH） and p-toluenesulfonic acid （TsOH） were also explored for preparing these products in ionic liquid. The catalysts and ionic liquid can be easily recovered and reused.

关键词： Tetrahydrofuran and tetrahydropyran derivatives tungstophosphoric acid ionic liquid catalyst synthesis

Intrinsic chemiluminescence production from the degradation of haloaromatic pollutants during environmentally-friendly advanced oxidation processes:Mechanism,structure-activity relationship and potential applications

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Journal of Environmental Sciences 2017年第12期29卷 68-83页

作者： Benzhan Zhu chen shen Huiying Gao Liya Zhu Jie Shao Li Mao State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences and University of Chinese Academy of SciencesChinese Academy of SciencesBeijing 100085China

The ubiquitous distribution of halogenated aromatic compounds（XAr） coupled with their carcinogenicity has raised public concerns on their potential risks to both human health and the ecosystem. Recently, advanced oxidation processes（AOPs） have been considered as an＂environmentally-friendly＂ technology for the remediation and destruction of such recalcitrant and highly toxic XAr. During our study on the mechanism of metal-independent production of hydroxyl radicals（UOH） by halogenated quinones and H_2O_2, we found, unexpectedly, that an unprecedented UOH-dependent two-step intrinsic chemiluminescene（CL） can be produced by H_2O_2 and tetrachloro-p-benzoquinone, the major carcinogenic metabolite of the widely used wood preservative pentachlorophenol. Further investigations showed that, in all UOH-generating systems, CL can also be produced not only by pentachlorophenol and all other halogenated phenols, but also by all XAr tested. A systematic structure–activity relationship study for all 19 chlorophenolic congeners showed that the CL increased with an increasing number of Cl-substitution in general. More importantly, a relatively good correlation was observed between the formation of quinoid/semiquinone radical intermediates and CL generation. Based on these results, we propose that UOH-dependent formation of quinoid intermediates and electronically excited carbonyl species is responsible for this unusual CL production; and a rapid, sensitive,simple, and effective CL method was developed not only to detect and quantify trace amount of XAr, but also to provide useful information for predicting the toxicity or monitoring real-time degradation kinetics of XAr. These findings may have broad chemical, environmental and biological implications for future studies on halogenated aromatic persistent organic pollutants.

关键词： Halogenated phenols Halogenated quinoid intermediates Semiquinone radical Hydroxyl radicals Fenton reaction Chemiluminescene method

Preparation and physicochemical effects of zein nanofiber membrane encapsulated with citral/HP-β-CD inclusion complex and its application on cheese

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Food Bioscience 2022年第6期50卷 107-117页

作者： chen shen Wenqing chen Changzhu Li Yong Ye Haiying Cui Lin Lin School of Food and Biological Engineering Jiangsu UniversityZhenjiang212013China State Key Laboratory of Utilization of Woody Oil Resource Hunan Academy of ForestryChangsha410007China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou510640China

As a nutritious cold chain food,cheese is susceptible to Listeria monocytogenes *** order to prevent and control Listeria monocytogenes in cheese safely and efficiently,maintain the sensory quality during sale,this paper developed a novel nanofiber membrane with good mechanical strength,hydrophobicity,thermal stability,release performance and bacteriostatic performance as food active *** this study,zein was introduced and electrospun to form a reliable carrier to embed and deliver citral in the cavity of HP-β-CD(Hydroxypropyl-β-cyclodextrin).We found that the zein-based nanofiber membranes showed preferable tensile properties and hydrophobicity with 4%(w:v)addition of citral/HP-β-CD inclusion ***,the thermal stability and release property of citral were significantly improved by embedding in HP-β-CD and loading into zein-base nanofiber ***,after packaged by Zein nanofiber membrane encapsulated with citral/HP-β-CD inclusion complex under the storage conditions of 4°C and 12°C,the growth of Listeria monocytogenes in four kinds of cheeses was inhibited to a certain *** texture and sensory quality of the four cheeses at the two temperatures and the color quality under the low temperature condition of 4°C did not change *** summary,Zein nanofiber membranes encapsulated with citral/HP-β-CD inclusion complex has potential application prospects in the field of food active packaging.

关键词： Zein Citral Hydroxypropyl-β-cyclodextrin Nanofiber membranes Hybrid electrospinning

Reliability of dermatomal somatosensory-evoked potential in the evaluation of lumbosacral nerve root injury A concurrent case-control study

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Neural Regeneration Research 2008年第1期3卷 57-60页

作者： Ningjiang shen Jian chen Guangji Wang Xiaoli Wu Yutian Wang Department of Orthopaedic Surgery Hainan Provincial People＇s Hospital Haikou 570311 Hainan Province China

BACKGROUND： It has been reported that dermatomal somatosensory evoked potential （DSEP） can be used for diagnosing nerve root injury in patients with lumbar disc herniation （LDH）, and that 83% 95% of patients suffer from the disease. Body height correction is not performed prior to determinations of latency and latency difference between the healthy and affected sides. However, latency noticeably correlates to body height. OBJECTIVE： This study aims to determine the lumbosacral nerve root injury in patients with LDH by DSEP, and to evaluate the sensitivity of the DSEP difference between the healthy and affected sides using a diagnostic index following body height correction. DESIGN： A case-control observation. SETTING： Department of Orthopedic Surgery, Hainan Provincial People＇s Hospital. PARTICIPANTS： Ninety-six patients, comprised of 67 males and 29 females, with an average age of 43 years and a mean body height of 1.65 m （range 1.48-1.81 m）, were recruited for this study. These patients suffered from unilateral lower limb radiation pain and received treatment at the Department of Orthopedic Surgery, Hainan Provincial People＇s Hospital between January 2004 and December 2006. All patients were confirmed to suffer from LDH at the L3-4, L-5, and/or Ls-SI by CT and/or MRI examinations. Central nervous system diseases were excluded. In order to obtain a normal reference value, DSEP was determined for a group of 50 subjects, who concurrently received health examinations in the same department. The subjects had no previous history of back leg pain or nervous system disease. The group of healthy controls included 26 males and 24 females, with an average age of 37 years and a mean body height of 1.63 m （range 1.50-1.80 m）. Written informed consent was obtained from all subjects for laboratory samples. The protocol was approved by the Hospital＇s Ethics Committees. DSEP was determined with myoelectricity-evoked potential equipment （Keypoint, Batch No. 9020A0042591, Dantec Com

关键词： dermatomal somatosensory evoked potential lumbar disc herniation nerve root injury