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Measuring radial Young’s modulus of DNA by tapping mode AFM

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Chinese Science Bulletin 2007年第23期52卷 3189-3192页

作者： lin Yi SHEN XinCheng WANG JingJing BAO Lei zhang Zhiling PANG DaiWen College of Chemistry and Molecular Sciences State Key Laboratory of Virology Wuhan University Wuhan 430072 China

Based on tapping mode AFM imaging, a method was demonstrated to evaluate compression elasticity of single double-stranded DNA (dsDNA) molecules in the force region. With images under ambient conditions, Young’s moduli of dsDNA in compression were calculated. Results demonstrated that Young’s moduli of dsDNA can be simply deduced according to the proposed model. The method can also be used to evaluate the compression elasticity of similar soft nanomaterials.

关键词：测量光线抽头模型弹性显微镜

Theoretical study of BTF/TNA cocrystal: Effects of hydrostatic pressure and temperature

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Defence Technology（防务技术） 2015年第2期11卷 132-139页

作者： Peng-yuan CHEN lin zhang Shun-guan ZHU Guang-bin CHENG School of Chemical Engineering Nanjing University of Science and Technology

Cocrystallization is a promising technique for the design and preparation of new explosives,and the stability of cocrystal is highly concerned by the *** order to make a better understanding of the behavior of cocrystal under the extreme conditions,DFT(density functional theory) calculation is performed to investigate the effect of hydrostatic pressure on geometrical and electronic structures of the cocrystal BTF(benzotrifuroxan)/TNA(2,4,6-trinitroaniline).When the hydrostatic pressure is applied,the lattice constants,volume,density and total energy change gradually except at the pressures of 40 GPa and 79e83 *** is noteworthy that new chemical bonds form when the pressure is up to83 *** band gap of the cocrystal becomes smaller when the pressure is applied,and finally the cocrystal shows a characteristic of *** mechanical property of cocrystal is calculated by MD(molecular dynamics) *** results show that the cocrystal has a better ductibility at low temperature,and has the best tenacity at 295 K.

关键词：静水压力共结晶 BTF TNA 密度泛函理论温度模拟计算分子动力学

Combination of artificial zeolite and microbial fertilizer to improve mining soils in an arid area of Inner Mongolia,China

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Journal of Arid Land 2023年第9期15卷 1067-1083页

作者： LI Wenye zhang Jianfeng SONG Shuangshuang LIANG Yao SUN Baoping WU Yi MAO Xiao lin Yachao School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China China ENFI Engineering Co. Ltd.Beijing 100038China PIESAT Information Technology Co. Ltd.Beijing 100195China Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Shanxi Dadi Minji Ecological Environment Co. Ltd.Beijing BranchBeijing 100083China Bureau of Agriculture and Rural Affairs Wangcheng DistrictChangsha 410211China

Restoration of mining soils is important to the vegetation and *** study aimed to explore the variations in soil nutrient contents,microbial abundance,and biomass under different gradients of substrate amendments in mining soils to select effective *** samples were collected from the Bayan Obo mining region in Inner Mongolia Autonomous Region,*** of soil organic matter(SOM),available nitrogen(AN),available phosphorus(AP),available potassium(AK),microbial biomass carbon/microbial biomass nitrogen(MBC/MBN)ratio,biomass,and bacteria,fungi,and actinomycetes abundance were assessed in Agropyron cristatum ***.,Elymus dahuricus Turcz.,and Medicago sativa *** with artificial zeolite(AZ)and microbial fertilizer(MF)applied at T0(0 g/kg),T1(5 g/kg),T2(10 g/kg),and T3(20 g/kg).Redundancy analysis(RDA)and technique for order preference by similarity to ideal solution(TOPSIS)were used to identify the main factors controlling the variation of *** showed that chemical indices and microbial content of restored soils were far greater than those of *** application of AZ significantly increases SOM,AN,and AP by 20.27%,23.61%,and 40.43%,*** significantly increased bacteria,fungi,and actinomycetes abundance by 0.63,3.12,and 1.93 times of control,*** indicated that AN,MBC/MBN ratio,and SOM were dominant predictors for biomass across samples with AZ application,explaining 87.6%of the biomass ***,MBC/MBN ratio,and AK were dominant predictors with MF application,explaining 82.9%of the biomass *** indicated that T2 was the best dosage and the three plant species could all be used to repair mining *** and MF application at T2 concentration in the mining soils with *** was found to be the most appropriate measure.

关键词： amendment arid area mining soils restoration soil nutrition

Response of ecosystem carbon storage to land use change from 1985 to 2050 in the Ningxia Section of Yellow River Basin,China

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Journal of Arid Land 2024年第1期16卷 110-130页

作者： lin Yanmin HU Zhirui LI Wenhui CHEN Haonan WANG Fang NAN Xiongxiong YANG Xuelong zhang Wenjun College of Geographical Sciences and Planning Ningxia UniversityYinchuan 750021China China-Arab Joint International Research Laboratory for Featured Resources and Environmental Governance in Arid Region Yinchuan 750021China Ningxia Land Resources Surveying and Monitoring Institute Yinchuan 750002China State Key Laboratory of Efficient Production of Forest Resources Yinchuan 750002China Ningxia lingwu Baijitan National Nature Reserve Administration Yinchuan 751400China

Regional sustainable development necessitates a holistic understanding of spatiotemporal variations in ecosystem carbon storage(ECS),particularly in ecologically sensitive areas with arid and semi-arid *** this study,we calculated the ECS in the Ningxia Section of Yellow River Basin,China from 1985 to 2020 using the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model based on land use *** further predicted the spatial distribution of ECS in 2050 under four land use scenarios:natural development scenario(NDS),ecological protection scenario(EPS),cultivated land protection scenario(CPS),and urban development scenario(UDS)using the patch-generating land use simulation(PLUS)model,and quantified the influences of natural and human factors on the spatial differentiation of ECS using the geographical detector(Geodetector).Results showed that the total ECS of the study area initially increased from 1985 until reaching a peak at 402.36×10^(6) t in 2010,followed by a decreasing trend to *** spatial distribution of ECS was characterized by high values in the eastern and southern parts of the study area,and low values in the western and northern *** 1985 and 2020,land use changes occurred mainly through the expansion of cultivated land,woodland,and construction land at the expense of unused *** total ECS in 2050 under different land use scenarios(ranked as EPS>CPS>NDS>UDS)would be lower than that in *** light was the largest contributor to the spatial differentiation of ECS,with soil type and annual mean temperature being the major natural driving *** of this study could provide guidance on the ecological construction and high-quality development in arid and semi-arid areas.

关键词： carbon storage land use change nighttime light Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model patch-generating land use simulation(PLUS)model geographical detector(Geodetector) Yellow River Basin

Polyhexamethylene biguanide chemically modified cotton with desirable hemostatic,inflammation-reducing,intrinsic antibacterial property for infected wound healing

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Chinese Chemical Letters 2022年第6期33卷 2975-2981页

作者： Chuan Guo Jie zhang Xiaojun Feng Zhenggui Du Yuanzhang Jiang Yidong Shi Guanghui Yang lin Tan College of Biomass Science and Engineering Key Laboratory of Leather Chemistry and Engineering of Ministry of EducationSichuan UniversityChengdu 610065China Department of Breast Surgery West China HospitalSichuan UniversityChengdu 610041China School of Materials and Environmental Engineering Shenzhen PolytechnicShenzhen 518000China State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengdu 610065China

Medical cotton dressing is cheap and widely used in diversified fields,but in the application of promoting wound healing,the continuous research of multifunctional medical cotton dressing is still of great ***,we developed a fresh type of antibacterial cotton dressing through a succinct strategy based on chemically anchoring polyhexamethylene biguanide(PHMB).Intriguingly,after PHMB modification,the cotton dressing exhibited outstanding antibacterial performance which could maintain>99.99%antibacterial rate after several treatments,including washing 50 times,repeated use 10 times,UV irradiation for 7 days,cationic dyes dying,and conditioned under 90℃water bath for 2 *** addition,the water contact angle of cotton dressing increased dramatically from 0°to 111°,which could facilitate bacterial adhesion,thus further enhance the antibacterial efficiency,and easily remove the bacterial *** from that,the developed cotton dressing showed good cytocompatibility,promoted blood clotting and expression of platelets,and promoted the wound healing process in the infection intervened skin wound *** together,this antibacterial cotton dressing with desirable blood clotting,sustained protection against bacterial infection and bacterial removal features shows the potential to be a candidate for infected skin wound healing.

关键词： Cotton dressing Polyhexamethylene biguanidine Antibacterial performance Blood clotting Infected wound healing

Formation mechanisms and control method for stray grains at melt-back region of Ni-based single crystal seed

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Progress in Natural Science:Materials International 2021年第4期31卷 624-632页

作者： Songsong Hu Wenchao Yang Zhuoran Li Hanyuan Xu Taiwen Huang Jun zhang Haijun Su lin Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical University School of Materials Science and Engineering Xiangtan University

An experimental study together with numerical simulation was conducted to investigate the formation mechanisms and control methods for stray grains at melt-back of seed in this paper. The numerical simulation results showed that the convex solid/liquid(S/L) interface changed very slowly into a concave interface during the initial solidification stage and the undercooling was slightly affected by the S/L curvature change. The formation of stray grains below melt-back interface at seed perimeter could be suppressed with the decrease of clearance between the seed and mold. However when the clearance was further decreased to 0, an orientation deviation layer formed originated from the deformation of un-melted seed caused by different expend coefficient between the seed and mold. The nucleation of stray grains above the melt-back interface at the seed perimeter could be suppressed using the mold with small surface roughness. The isolated un-melted dendrite stem at semi-solid mushy of the seed with the large original primary dendrite spacing transfer to complex network structure, suppressing the formation of the stray grains, when the primary dendrite spacing of seed decreased or the seed underwent solution heat treatment. Then, the formation mechanisms of the stray grains at the melt-back region are discussed based on above results, and a method is proposed to suppress the formation of the stray grains for preparing single crystal components by re-used seed.

关键词： Ni-based single crystal superalloys Directional solidification Solidification defects Solid/liquid interface Seeds Numerical simulation

The optical phonon drag effect on strong-coupling decay magnetopolaron in Gaussian alkali halogen ionic quantum wells

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Communications in Theoretical Physics 2023年第5期75卷 167-172页

作者： Yong Sun Ran An Wei zhang Shuang Han Xin-Jun Ma Pei-fang Li Jing-lin Xiao Institute of Condensed Matter Physics Inner Mongolia Minzu University(Inner Mongolia University for Nationalities)Tongliao 028043China

The polaron phenomenon is commonly observed in low-dimensional semiconductor materials and is known to have unique effects on conductive material ***,the phonon dragging effect,which leads to the polaron energy level,is less than the electron energy level.A decay magnetic field also affects the polaron effect,which causes polaron energy level *** demonstrate the unique electron-phonon coupling properties of this polaron using numerical *** findings have strong implications for theories of polaron properties and provide compelling evidence for a semiconductor device that industrial manufacturers use for new lowdimensional materials.

关键词： asymmetric Gaussian confinement potential decay magnetic field strong-coupling crystals quantum well magnetopolaron

Retroperitoneal cavernous hemangioma misdiagnosed as lymphatic cyst:A case report and review of the literature

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World Journal of Clinical Cases 2023年第15期11卷 3560-3570页

作者： Xiao-Fan Hou Zhan-Xue Zhao lin-Xun Liu Hao zhang Medical College Qinghai UniversityXining 810000Qinghai ProvinceChina Department of General Surgery Qinghai Provincial People's HospitalXining 810000Qinghai ProvinceChina

BACKGROUND Primary abdominal and retroperitoneal cavernous hemangioma is a vascular tumor and rarely seen in the *** to the lack of specific imaging features,retroperitoneal cavernous hemangioma cannot be diagnosed *** symptoms may develop with the enlargement of lesion volume or the occurrence of complications such as rupture or *** report here a special case who was admitted with chronic abdominal *** examination suggested a retroperitoneal lymphatic duct *** resection of the retroperitoneal mass was performed,and histological examination confirmed retroperitoneal cavernous *** SUMMARY The patient was a 43-year-old Tibetan woman with intermittent left lower abdominal pain and discomfort 3 years *** revealed a cystic mass in the retroperitoneum with clear boundaries,internal septa,and no blood flow *** tomography(CT)and magnetic resonance imaging(MRI)showed an irregular space-occupying mass in the retroperitoneum,and retroperitoneal lymphatic cyst was *** CT scanning showed multiple cystlike hypo-intense shadows in the retroperitoneum,partially fused into a mass,and no obvious enhancement was found on enhanced *** showed multiple irregular clump-like long T1 and long T2 signal shadows above the pancreas,within which linear short T2 signal shadows were *** imaging sequence showed hypo-signal shadows,without obvious enhancement on enhanced ***,CT,and MRI all suggested the possibility of retroperitoneal lymphatic ***,the patient was finally diagnosed with retroperitoneal cavernous hemangioma by pathological *** Retroperitoneal cavernous hemangioma is a benign lesion,and it is difficult to make a diagnosis *** resection may be the only treatment,which not only allows histopathological confirmation as a diagnostic purpose and excludes any risk of malignancy,but also avoids i

关键词： Cavernous hemangioma Retroperitoneal Diagnosis Treatment Case report

Evaluating the predictive factors of resting energy expenditure and validating predictive equations for Chinese obese children

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World Journal of Pediatrics 2018年第2期14卷 160-167页

作者： lin zhang Ran Chen Rong Li Meng-Ying Chen Rong Huang Xiao-Nan Li Department of Children Health Care Chilren's hospital affiliated with Nanjing medical university72 Guangzhou RoadNanjing 210008China

Background To study the predictive factors of resting energy expenditure(REE)and evaluate the accuracy of predicted equations with indirect calorimeter(IC)in Chinese school-age children,particularly for the obese *** Recruited children were from the department of child healthcare in Nanjing children's hospital during July 2014-September *** parameters and body composition were measured by bioelectrical *** REE was assessed by *** REE was estimated using ten published *** 248 children aged 7-13 years were recruited,including 148 obese[body mass index standard deviation score(BMISDS)=2.48±0.91]and 100 non-obese(BMISDS=-0.96±1.08).The unit mass of REE(REE/kg)in obese group(29.06±5.74)was lower than that in non-obese group(37.51±6.56).The stepwise regression showed that age,BMISDS and fat-free mass(FFM)had a major impact on REE/kg as the regression equation:Y=54.41-1.36×X_(1)-2.25×X_(2)-0.16×X_(3)(Y REE/kg,X_(1)age,X_(2)BMISDS,X_(3)FFM;R=0.633,R^(2)=0.401,P<0.01).The accuracy of predicted REE in obese subjects was 62.16%by the new predictive *** The REE/kg in obese children was lower and closely correlated with age,BMISDS and *** is necessary to validate the new predictive equation in a larger sample to estimate energy requirements,particularly for children with obesity.

关键词： Chinese children Energy expenditure Nutrition Obesity