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Liquid exfoliation of stanene as degradable nanoagents for NIR-II photothermal therapy

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Journal of Materials Science & Technology 2023年第17期148卷 186-198页

作者： xueqiao Li Weijian Li Zhaohua Miao Chenxi Lu Hongna Ma yan xu Deyan Gong cheng-yan xu Zhengbao Zha School of Food and Biological Engineering Hefei University of TechnologyHefei 230009China College of Nuclear Equipment and Nuclear Engineering Yantai UniversityYantai 264005China School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China Shenzhen Bay Laboratory Shenzhen 518052China

Stanene,the two-dimensional form of elemental tin(Sn),is easily oxidized in the ambient environ-ment,significantly hindering its applications in biomedical ***,the degradation mechanism of stanene remains ***,combined DFT calculations and proof-of-concept experiments were conducted to elucidate the underlying degradation mechanism of *** results reveal that the degradation of stanene in an oxygenated water environment is a water-accelerated oxidation process.H_(2) O molecules could not only facilitate the electron transfer from stanene to O_(2) because of the polarization effect of H_(2) O,but also directly react with the defect sites of stanene due to enhanced absorption ***,several protective strategies like alcohol protection were proposed to avoid or mitigate the oxidation of stanene for further ***,stanene was explored as the second near-infrared(NIR-II)photonic agents for ablation of 4T1 tumor,depicting a tumor-growth inhibition ratio up to 96.7%,much better than that of the first near-infrared(NIR-I)group(65.5%).This work reveals the degradation mechanism of stanene and demonstrates its biomedical applications in the NIR-II region.

关键词： Stanene Degradation mechanism DFT calculations Photothermal therapy NIR-II

Study on the strength of cold-bonded high-phosphorus oolitic hematite-coal composite briquettes

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International Journal of Minerals,Metallurgy and Materials 2014年第5期21卷 423-430页

作者： Wen Yu Ti-chang Sun Zhen-zhen Liu Jue Kou cheng-yan xu The Key Laboratory of the Ministry of Education of China for High-Efficient Mining and Safety of Metal Mines University of Science and Technology Beijing School of Civil and Environmental Engineering University of Science and Technology Beijing

Composite briquettes containing high-phosphorus oolitic hematite and coal were produced with a twin-roller briquette machine using sodium carboxymethyl cellulose, molasses, starch, sodium silicate, and bentonite as binders. The effect of these binders on the strength of the composite briquettes, including cold strength and high-temperature strength, was investigated by drop testing and compression testing. It was found the addition of Ca（OH）2 and Na2CO3 not only improved the reduction of iron oxides and promoted dephosphorization during the reduction-separation process but also provided strength to the composite briquettes during the briquetting process; a compressive strength of 152.8 N per briquette was obtained when no binders were used. On this basis, the addition of molasses, sodium silicate, starch, and ben- tonite improved the cold strength of the composite briquettes, and a maximum compressive strength of 404.6 N per briquette was obtained by using starch. When subjected to a thermal treatment at 1200~C, all of the composite briquettes suffered from a sharp decrease in compressive strength during the initial reduction process. This decrease in strength was related to an increase in porosity of the composite briquettes. X-ray diffraction （XRD） and scanning electron microscopy （SEM） analyses showed that the decrease in strength of the composite briquettes could be caused by four factors： decomposition of bonding materials, gasification of coal, transportation of byproduct gases in the composite briquettes, and thermal stress.

关键词： hematite briquetting binders compressive strength porosity direct reduction process-

Effects of embedding direct reduction followed by magnetic separation on recovering titanium and iron of beach titanomagnetite concentrate

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Journal of Iron and Steel Research International 2017年第2期24卷 156-164页

作者： Chao Geng Ti-chang Sun You-wen Ma cheng-yan xu Hui-fen yang School of Civil and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China

Embedding direct reduction followed by magnetic separation was conducted to fully recover iron and titanium separately from beach titanomagnetite （TTM）. The influences of reduction conditions, such as molar ratio of C to Fe, reduction time, and reduction temperature, were studied. The results showed that the TTM concentrate was reduced to iron and iron-titanium oxides, depending on the reduction time, and the reduction sequence at 1 200℃ was suggested as follows ： Fe2.75 Ti0.25O4→Fe2TiO4→FeTiO3→FeTi2O5. The reduction temperature played a considerable role in the reduction of TTM concentrates. Increasing temperature from 1 100 to 1 200℃ was beneficial to recovering titanium and iron, whereas the results deteriorated as temperature increased further. The results of X-ray diffraction and scanning electron microscopy analyses showed that low temperature （≤1100℃） was unfavorable for the gasification of reductant, resulting in insufficient reducing atmosphere in the reduction process. The molten phase was formed at high temperatures of 1250-1 300℃, which accelerated the migration rate of metallic particles and suppressed the diffusion of reduction gas, resulting in poor reduction. The optimum conditions for reducing TTM concentrate are as follows： molar ratio of C to Fe of 1.68, reduction time of 150 min, and reduction temperature of 1 200℃. Under these conditions, direct reduction iron powder, assaying 90.28 mass% TFe and 1.73 mass% TiO2 with iron recovery of 90.85%, and titanium concentrate, assaying 46.24 mass% TiO2 with TiO2 recovery of 91.15%, were obtained.

关键词： Titanomagnetite concentrate Direct reduction Reduction condition Direct reduction iron powder Magnetic separation

Effect of Sodium Sulfate on Direct Reduction of Beach Titanomagnetite for Separation of Iron and Titanium

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Journal of Iron and Steel Research International 2016年第5期23卷 428-433页

作者： En-xia GAO Ti-chang SUN Zhi-guo LIU Chao GENG cheng-yan xu School of Civil and Environmental Engineering University of Science and Technology Beijing

The effect of sodium sulfate on direct reduction of beach titanomagnetite,followed by magnetic separation,to separate iron and titanium was investigated. Direct reduced iron（ DRI） with a high Fe content,low TiO_2 content and low iron recovery was obtained after adding sodium sulfate. When the sodium sulfate dosage was increased from 0 to 10 mass%,the Fe content of the DRI increased from 90. 00 mass% to 93. 55 mass% and the TiO_2 content decreased from 1. 27 mass% to 0. 70 mass%. The reduction mechanism of sodium sulfate was investigated by X-ray diffraction（ XRD） and scanning electron microscopy（ SEM） with energy dispersive spectrometer（ EDS）. Results revealed that the metallic iron grains in the reduced ore with sodium sulfate were larger than those in the ore without sodium sulfate. Sodium sulfate promoted the migration of iron as well as the accumulation and growth of metallic iron grains by low-melting-point carnegieite and troilite formed in the redox system. Low-melting-point carnegieite decreased the melting point of the system and then promoted liquefaction. Troilite could decrease the surface tension and melting point of metallic iron grains.

关键词： beach titanomagnetite sodium sulfate direct reduction separation iron titanium

Three-dimensional regulation of transcription

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Protein & Cell 2015年第4期6卷 241-253页

作者： Jun Cao Zhengyu Luo Qingyu cheng Qianlan xu yan Zhang Fei Wang yan Wu Xiaoyuan Song CAS Key Laboratory of Brain Function and Disease and School of Life Sciences University of Science and Technology ofChina Hefei 230027 China

Cells can adapt to environment and development by reconstructing their transcriptional networks to regulate diverse cellular processes without altering the underly- ing DNA sequences. These alterations, namely epige- netic changes, occur during cell division, differentiation and cell death. Numerous evidences demonstrate that epigenetic changes are governed by various types of determinants, including DNA methylation patterns, his- tone posttranslational modification signatures, histone variants, chromatin remodeling, and recently discovered chromosome conformation characteristics and non- coding RNAs （ncRNAs）. Here, we highlight recent efforts on how the two latter epigenetic factors participate in the sophisticated transcriptional process and describe emerging techniques which permit us to uncover and gain insights into the fascinating genomic regulation.

关键词： transcriptional regulation long non-coding RNAs three-dimensional chromosome interactions,epigenetic changes

Enhanced proton irradiation resistance in Cs-doped CH_(3)NH_(3)PbI_(3) films and solar cells

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Journal of Energy Chemistry 2022年第6期31卷 261-269,I0008页

作者： Pan Luo xue-Yin Sun Hao Jiang Li yang yang Li Wen-Zhu Shao Liang Zhen cheng-yan xu School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001HeilongjiangChina National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001HeilongjiangChina MOE Key Laboratory of Micro-Systems and Micro-Structures Manufacturing Harbin Institute of TechnologyHarbin 150080HeilongjiangChina Sauvage Laboratory for Smart Materials School of Materials Science and EngineeringHarbin Institute of Technology(Shenzhen)Shenzhen 518055GuangdongChina

Mixed-cation perovskite solar cells have attracted tremendous attention in space applications due to their excellent power conversion efficiency (PCE) and stability to light and *** the evolution of photovoltaic performance in different space environments has been investigated,the role of inorganic cesium ions (Cs^(+)) in the enhancement of irradiation resistance needs to be further ***,the structure and performance evolution of Cs-doped CH_(3)NH_(3)PbI_(3)(MAPbI_(3)) films and planar heterojunction devices under proton irradiation up to 1×10^(16)p cm^(-2) were studied.5%of Cs^(+) doping can increase the cohesive energy of MAPbI_(3)and effectively alleviate the lattice strain induced by proton irradiation,thereby enhancing the crystallinity and stability of *** bandgap changes of irradiated Cs_(0.05)MA_(0.95)PbI_(3) films under the identical fluence were only one third of that of MAPbI_(3) *** irradiation under the fluence of 1×10^(14)p cm^(-2),the density of trap states in the undoped and 5%Cs-doped films increased by 71%and 9%,respectively,and the average PCE of 20 corresponding devices decreased only by 12%and 9%,*** proves that the replacement of organic methylamine ion with inorganic cesium ion contributes to the improvement of MAPbI_(3) resistance to proton irradiation,thus confirming the application prospects of mixed-cation or all-inorganic perovskite solar cells in spacecraft.

关键词： Proton irradiation Perovskite solar cells Cesium doping Irradiation resistance

In-situ growth of CNTs encapsulating P-doped NiSe_(2) nanoparticles on carbon framework as efficient bifunctional electrocatalyst for overall water splitting

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Journal of Energy Chemistry 2021年第9期30卷 111-120页

作者： Jing Yu Wei-Jian Li Guibo Kao cheng-yan xu Rongrong Chen Qi Liu Jingyuan Liu Hongsen Zhang Jun Wang Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China College of Nuclear Equipment and Nuclear Engineering Yantai UniversityYantai 264005China

Nickel diselenide(NiSe_(2)) is a promising low-cost catalyst for both hydrogen evolution reaction(HER) and oxygen evolution reaction(OER),due to its suitable d-electron configuration and high electrical *** representative elements,e.g.,Co,Fe and P,have been utilized as cation or anion to promote the electrocatalytic activity of NiSe_(2) by modulating the interaction with Se element,whilst the catalyst stability is less *** this work,the catalytic Ni nanoparticles were in-situ encapsulated in carbon nanotubes grown on three-dimensional conducting carbon *** phosphorization and selenization yield dispersed P-doped NiSe_(2) nanoparticles protected by carbon shell with highly exposed yet stable active sides,resulting in significantly promoted HER and OER activities as well as accelerated *** detail,the P-NiSe_(2)@N-CNTs/NC hybrid catalyst deliver low overpotentials of 95 and 306 mV at10 mA cm^(-2) for HER and OER in alkaline media,*** calculations reveal that P doping reduces the electron density surrounding Ni atoms while accumulates the charges to Se, respectively,which in turn reduces the energy barriers for both water dissociation and intermediates adsorption for both HER and *** a concept of proof,a cell assembled by P-NiSe_(2)@N-CNTs/NC hybrid catalystbased anode and cathode performs a low applied voltage of 1.609 V to reach 10 mA cm^(-2),and outstanding long-term stability.

关键词： Electrocatalyst NiSe_(2) Doping Water splitting DFT calculations

Decline of semen quality among Chinese sperm bank donors within 7 years （2008-2014）

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Asian Journal of Andrology 2017年第5期19卷 521-525页

作者： Li Wang Lin Zhang Xiao-Hui Song Hao-Bo Zhang cheng-yan xu Zi-Jiang Chen Center for Reproductive Medicine Shandong Provincial Hospital Affiliated to Shandong University Jinan China Shandong Provincial Key Laboratory of ReproductiveMedicine Jinan China National Research Center for Assisted Reproductive Technology and Reproductive Genetics Jinan China Key Laboratory for ReproductiveEndocrinology of Ministry of Education Jinan China

Semen from 5210 sperm bank donors was analyzed and trends in semen quality were evaluated at Shandong Human Sperm Bank between 2008 and 2014. After 2-7 days of abstinence, semen samples were collected. Measurements of semen volume, sperm concentration, sperm forward motility, and total sperm count were performed. There were significant declining trends in semen volume, sperm concentration, sperm forward motility, and total sperm count. Our results indicate that the quality of semen in this cohort of sperm donors had decreased during the study period.

关键词： male infertility semen quality sperm donation

Obesity and colorectal cancer risk: A meta-analysis of cohort studies

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World Journal of Gastroenterology 2007年第31期13卷 4199-4206页

作者： Zhe Dai yan-cheng xu Li Niu DepartmentofEndocrinology ZhongnanHospitalWuhanUniversityWuhan430071HubeiProvinceChina

TO evaluate the association between obesity and colorectal cancer risk. METHODS： We searched PubMed, EMBASE, and the Cochrane Library up to January 1, 2007. Cohort studies permitting the assessment of causal association between obesity and colorectal cancer, with clear definition of obesity and well-defined outcome of colorectal cancer were eligible. Study design, sample size at baseline, mean follow-up time, co-activators and study results were extracted. Pooled standardized effect sizes were calculated.

关键词： Obesity Colorectal cancer Waist-to-hipratio Waist circumference Weight Cohort study Metaanalysis