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Interaction of Photoactive[Fe(CN)_6]^(4-) with TiO_2 Anatase(101) Surface:A Periodic Density Functional Theory Study

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Chinese Journal of Structural Chemistry 2007年第3期26卷 361-366页

作者： XU ying chen wen-Kai CAO Mei-Juan LIU Shu-Hong LI Jun-Qian Department of Chemistry Fuzhou University Fuzhou Fujian 350002 China

The plane-wave pseudopotential function method, based on density-functional theory, has been used to calculate the adsorption, electronic band structures, orbitals and optical absorption spectrum of [Fe（CN）6]^4- on TiOz anatase（101） surface. Our calculations reveal that the surface-modified anatase system has large adsorption energy and a much narrower band gap. [Fe（CN）6]^4- adsorption on the （101） surface could lead to a large red shift of the anatase optical absorption threshold, which extends into a visible region significantly. The calculated results are in agreement with the experiment and other theoretical studies reasonably. It is very important for the understanding and further development ofphotovoltaic materials that are active under visible light.

关键词： density functional theory (DFT) [Fe(CN)6]^4- anatase(101) surface adsorption absorption

An adpA homologue in Streptomyces avermitilis is involved in regulation of morphogenesis and melanogenesis

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Chinese Science Bulletin 2007年第5期52卷 623-630页

作者： ZHAO JinLei wen ying chen Zhi SONG Yuan LI JiLun Department of Microbiology and Immunology College of Biological Sciences China Agricultural University and Key Laboratory of Agro-Microbial Resource and Application Ministry of Agriculture Beijing 100094 China

In Streptomyces griseus, AdpA, the key transcriptional activator in the A-factor regulatory cascade, switches on the transcription of multiple genes required for secondary metabolism and morphological differentiation. Streptomyces avermitilis also contains an ortholog of adpA, which is named adpA-a. To clarify the in vivo function of adpA-a, an adpA-a-disrupted strain was constructed by double crossover recombination. No difference in avermectin production was found between the adpA-a-disruptant and the wild-type strain. However, this disruptant neither formed spores nor produced melanin and its phenotype was restored to the original wild-type by a single copy of the adpA-a gene integrated into the chromosome. This report shows that adpA-a is involved in regulation of morphological differentiation and melanin production in S. avermitilis.

关键词：灰色链霉菌除虫链霉菌黑素生成 AdpA同族体转化致活因子形态发生次级代谢

Electron paramagnetic resonance study of amphiphiles partitioning behavior in desiccation-tolerant moss during dehydration

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Chinese Chemical Letters 2007年第7期18卷 865-868页

作者： Shu Jun Xu Wei Hong chen ying wen chen Cui Fang Wang Yan Wang School of Environmental Science and Engineering Shanghai Jiaotong University Shanghai 200240 China Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Desiccation tolerance is a crucial characteristic for desert moss surviving in arid regions. Desiccation procedure always induces amphiphiles transferring from the polar cytoplasm into lipid bodies. The behavior of amphiphiles transferring can contribute to the enhancement of desiccation tolerance and the reduction of plasma membrane integrity simultaneously. The effects of amphiphiles partitioning into the lipid phase during water loss has been studied for pollen and seeds using electron paramagnetic resonance （EPR） spectroscopy. However, desiccation-tolerant high plants occur among mosses, several angiosperms and higher plants seeds or pollens. They have different strategies for survival in dehydration and rehydration. A desiccation-tolerant moss Tortula desertorurn was used to investigate the behaviors of amphiphilic molecules during drying by spin label technology. There are small amount of amphiphilic probes partitioning into membrane during moss leaves dehydration, comparing with that in higher plants. Cytoplasm viscosity changed from 1.14 into glass state only dehydration less than 60 min. Moss leaves lost plasma membrane integrity slightly,from 0.115 to 0.237, occurred simultaneously with amphiphiles partition. The results showed the more advantages of mosses than higher plants in adapting fast dehydration. We propose that EPR spin label is feasible for studying the amphiphiles partitioning mechanisms in membrane protection and damage for desiccation-tolerant mosses.

关键词： Plasma membrane permeability Amphiphiles partition Desiccation tolerance Electron paramagnetic resonance Tortula desertorum broth. Mosses

Effect of nano-carbon black content on wetting phenomenon of molten steel and alumina-carbon ceramic filter substrates

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Journal of Iron and Steel Research International 2024年第8期31卷 1900-1913页

作者： Jin-wen Song wen Yan Zhe chen ying Liu Shao-song Hong The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina National-provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology Wuhan University of Science and TechnologyWuhan 430081HubeiChina Jiangsu Sheng Nai New Materials Co. Ltd.Taizhou 225503JiangsuChina

The effect of nano-carbon black content(O,8 and 12 wt.%)on the wettability of molten steel on Al_(2)O_(3)-C substrates was investigated by the sessile drop wetting method at 1500℃ under argon *** the beginning of the wetting experiment,the contact angle decreased with the increase in nano-carbon black *** the wetting experiment progressed,FeAl_(2)0_(4) layer and sheet Al_(2)O_(3) layer were found at the interface between the molten steel and the Al_(2)O_(3)-C substrates with O and 8 wt.% nano-carbon black content,and the contact angle deceased with *** the content of nano-carbon black was 12 wt.%,a large number of nano-Al_(2)O_(3) whiskers were observed,which made the contact angle between the molten steel and Al_(2)O_(3)-C substrate become *** on the scanning electron microscope and energy dispersive spectrometry results,the formation mechanism of FeAl2O4 layer and Al_(2)O_(3) layer and the interfacial reaction mechanism were proposed.

关键词： Contact angle Nano-carbon black Al_(2)O_(3)-C substrate Molten steel Interfacial reaction

Relationship between hyperuricemia and metabolic syndrome

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第8期8卷 593-598页

作者： chen Li-ying ZHU wen-hua chen Zhou-wen DAI Hong-lei REN Jing-jing chen Jian-hua chen Lei-qian FANG Li-zheng Department of Family Medicine Sir Run Run Shaw Hospital School of Medicine Zhejiang University Hangzhou 310016 China

Objective: To investigate the relationship between metabolic syndrome and hyperuricemia. Methods: A total of 2 374 subjects who received health examination in our hospital from Jan. 2004 to Dec. 2006 were enrolled in our study. Hyperuricemia is defined as ≥7 mg/dl (in men) or ≥6.0 mg/dl (in women). Metabolic syndrome was defined using AHA/NHLBI (American Heart Association/National Heart, Lung, and Blood Institute) criteria. Results: (1) The overall prevalence of hyperuricemia was 13.10%. The condition was more common in men than in women (19.07% vs 3.42%). (2) Among men, uric acid concentration is statistically significantly positively correlated with waist circumference, blood pressure, and triglyceride. Uric acid is negatively correlated with serum high-density lipoprotein-cholesterol (HDL-C). Uric acid concentration is most strongly correlated with serum triglyceride (r=0.379) and waist circumference (r=0.297). Among women, statistically significant positive correlations were noted for the serum uric acid concentrations with waist circumference, triglyceride and fasting plasma glucose. Serum triglyceride (r=0.329) and waist circumference (r=0.234) are most strongly correlated with uric acid concentrations. (3) Men with hyperuricemia had a 1.634-fold increased risk of metabolic syndrome as compared with those without hyperuricemia odds ratio (OR)=1.634, P=0.000. Women with hyperuricemia had a 1.626-fold increased risk of metabolic syndrome (OR=1.626, P=0.000) as compared with those without hyperuricemia. Conclusion: Hyperuricemia is prevalent among Chinese population. Additionally, serum uric acid is positively associated with metabolic syndrome.

关键词： Hyperuricemia Metabolic syndrome Triglyceride

Quantitative prediction model for the depth limit of oil accumulation in the deep carbonate rocks:A case study of Lower Ordovician in Tazhong area of Tarim Basin

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Petroleum Science 2024年第1期21卷 115-124页

作者： wen-Yang Wang Xiong-Qi Pang Ya-Ping Wang Zhang-Xin chen Fu-Jie Jiang ying chen State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Research Institute of Exploration and Development PetroChina Southwest Oil&Gas Field CompanyChengdu610041SichuanChina Chemical and Petroleum Engineering Schulich School of EngineeringUniversity of CalgaryCalgaryT2N 1N4Canada

With continuous hydrocarbon exploration extending to deeper basins,the deepest industrial oil accumulation was discovered below 8,200 m,revealing a new exploration ***,the extent to which oil exploration can be extended,and the prediction of the depth limit of oil accumulation(DLOA),are issues that have attracted significant attention in petroleum *** it is difficult to characterize the evolution of the physical properties of the marine carbonate reservoir with burial depth,and the deepest drilling still cannot reach the ***,the DLOA cannot be predicted by directly establishing the relationship between the ratio of drilling to the dry layer and the *** this study,by establishing the relationships between the porosity and the depth and dry layer ratio of the carbonate reservoir,the relationships between the depth and dry layer ratio were obtained *** depth corresponding to a dry layer ratio of 100%is the *** on this,a quantitative prediction model for the DLOA was finally *** results indicate that the porosity of the carbonate reservoir,Lower Ordovician in Tazhong area of Tarim Basin,tends to decrease with burial depth,and manifests as an overall low porosity reservoir in deep *** critical porosity of the DLOA was 1.8%,which is the critical geological condition corresponding to a 100%dry layer ratio encountered in the *** depth of the DLOA was 9,000 *** study provides a new method for DLOA prediction that is beneficial for a deeper understanding of oil accumulation,and is of great importance for scientific guidance on deep oil drilling.

关键词： Deep layer Tarim Basin Hydrocarbon accumulation Depth limit of oil accumulation Prediction model

Purification performance on molten steel of novel Al_(2)O_(3)-based ceramic filter prepared from microporous powder and nano-Al_(2)O_(3) powder

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Journal of Iron and Steel Research International 2024年第6期31卷 1535-1546页

作者： Zhe chen wen Yan ying Liu Guang-qiang Li Shao-song Hong Nan Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Jiangsu Shengnai New Materials Co. Ltd.Taizhou 225534JiangsuChina

Reticulated ceramic foam filters provide an effective way to purify molten steel by removing non-metallic *** proposed a novel strategy to improve the purification performance of Al_(2)O_(3)-based ceramic filters by using microporous corundum-spinel raw materials to replace dense raw *** kinds of Al_(2)O_(3)-based ceramic filters fabricated from dense α-Al_(2)O_(3) micro-powder or microporous corundum-spinel powder were selected to carry out the immersion tests with molten *** the one hand,the higher surface roughness of the filter skeleton prepared from microporous raw materials increased the adsorption capacity of skeleton surface on inclusions in molten *** the other hand,the higher apparent porosity and larger pore size of the filter skeleton were more beneficial to the penetration of molten steel in the micropores of *** reaction process at the solid-liquid interface also improved the wettability of the interface between skeleton and molten steel,resulting in a larger penetration depth and a better adsorption effect on the *** summary,the novel Al_(2)O_(3)-based ceramic filter prepared with microporous corundum-spinel powder and addition of 5 wt.% nano-Al_(2)O_(3) powder reduced the total oxygen content of the steel from 40.2×10^(-4) to 12.7×10^(-4) wt.% by 68.4% and the Al content from 0.46 to 0.18 wt.% by 60.9% after immersion test,presenting the most excellent purification performance on molten steel.

关键词： Al_(2)O_(3)-based ceramic filter Microporous corundum-spinel powder Non-metallic inclusion-Microstructure Molten steel purification

Goal-Oriented Control Systems(GOCS):From HOW to WHAT

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 816-819页

作者： wen-Hua chen the Department of Aeronautical and Automotive Engineering Loughborough UniversityLeicestershireLE113TUU.K.

Brief:New control theory is required to underpin safe design and deployment of future highly automated systems to deal with uncertain environments and complicated tasks,enabled by AI and other advanced ***-Oriented Control Systems offer potential to transform the control system design from currently instructing a control system how to perform a task to specifying what is to be achieved.

关键词： automated instru system

Rational design of biodegradable semiconducting polymer nanoparticles for NIR-II fluorescence imaging-guided photodynamic therapy

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Nano Research 2024年第6期17卷 5399-5408页

作者： Xuxuan Gu Jinlong Shen Zhiwei Xu wenqi Wang ying Wu wen Zhou chen Xie Quli Fan State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials(IAM) Nanjing University of Posts&Telecommunications9 Wenyuan RoadNanjing 210023China

Semiconducting polymer nanoparticles(SPNs)have shown great promise in second near-infrared window(NIR-II)***,the issue of long metabolic time significantly restricts the clinical application of *** this study,we rationally designed a biodegradable SPN(BSPN50)for NIR-II fluorescence imaging-guided photodynamic therapy(PDT).BSPN50 is prepared by encapsulating a biodegradable SP(BSP50)with an amphiphilic copolymer ***50 is composed of NIR-II fluorescent diketopyrrolopyrrole(DPP)segment and degradable poly(phenylenevinylene)(PPV)segment with the ratio of 50/***50 has both satisfactory degradability under myeloperoxidase(MPO)/hydrogen peroxide(H_(2)O_(2))and NIR-II fluorescence emission upon 808 nm laser ***,BSPN50 shows good photodynamic efficacy under 808 nm laser ***50 shows a faster degradation rate than BSPN100 which has no PPV segment both in vitro and in *** addition,BSPN50 can effectively diagnose tumor via NIR-II fluorescence imaging and inhibit the tumor growth by ***,our study provides a rational approach to construct biodegradable nanoplatforms for efficient tumor NIR-II phototheranostics.

关键词： near-infrared(NIR)-II fluorescence imaging semiconducting polymer nanoparticles photodynamic therapy tumor imaging