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Chain Dynamics Heterogeneity in Plasticized Poly(vinyl butyral)(PVB) as Elucidated by Solid-State NMR

Chinese Journal of Polymer Science 2024年第1期42卷 113-124,I0010页

作者： Jing Lv Xu Chen Zi-Shuo Wu ya-hui li Wei Chen National Synchrotron Radiation Laboratory Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmCAS Key Laboratory of Soft Matter ChemistryUniversity of Scienceand Technology of ChinaHefei 230026China

The chain dynamics heterogeneity of the poly(vinyl butyral)(PVB) plasticized by triethylene glycol bis(2-ethylhexa noate)(TEG-EH) was investigated by various solid-state NMR *** plasticized PVB shows two domains in distinct molecular dynamics differences,namely,rigid and soft domains,where the latter is the plasticizer-rich *** time domain low field NMR was first used to investigate the dynamics heterogeneity of the plasticized PVB,and the results show the decreasing activated energy of components in the soft domain of plasticized PVB(E_a=20.2 kJ/mol) as compared with that of the pristine one(E_a=24.3 kJ/mol).Detailed dynamics heterogeneity was obtained by high-field NMR with site-specific *** quadrupole-echo ~2H-NMR was adopted to elucidate the dynamics heterogeneity of the vinyl alcohol(VA) units,where only the hydroxyl group of VA is *** ~1H-^(13)C WISE NMR spectra show that there is not much difference in the mobility of the VB unit in PVB with and without plasticizer,whereas the glass transition temperature differed by approximately 53℃.This is further supported by Torchia's T_1 relaxation *** origin of such an unusual phenomenon is attributed to the critical role of the remaining VA(~22%) in the soft domain,where the VA units locally aggregate through hydrogen ***,the existence of a mobility gradient in the VB unit has been ***,the mobility difference for VB with different stereo-geometry(meso or racemic conformation) is observed for the first *** indicates the importance of modulating the ratio of meso over racemic VB for controlling the macroscopic perfo rmance of PVB.

关键词： Poly(vinyl butyral) Dynamics heterogeneity Plasticizer Solid state NMR

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Optimization of flow uniformity control device for six-stream continuous casting tundish

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Journal of Iron and Steel Research International 2020年第9期27卷 1035-1044页

作者： Xin-gang Ai Dong Han Sheng-li li Hong-bo Zeng hui-ya li Key Laboratory of Chemical Metallurgy Engineering liaoning Province University of Science and Technology LiaoningAnshan 114051LiaoningChina

For a multistream tundish,the uniformity among the streams plays a significant role in the quality of molten *** to analyze the uniformity quantitatively and optimize structures of a multistream tundish is an important research content for a multistream tundish.A new approach was proposed to quantify the uniformity among the *** a physical study and a numerical study were carried out to optimize the structure of the diversion hole based on the prototype of a six-stream tundish in a steel *** the basis of average residence time,the uniformity of each flow was considered fully and then the optimal structure of the diversion hole was obtained by means of the comprehensive analysis of temperature field and velocity *** results show that the optimum structural parameters adopted for diversion holes are height of 20 mm,angle of 15°and diameter of 80 mm.

关键词： Multistream tundish Uniformity Diversion hole Physical simulation Numerical simulation

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Height and body mass index trajectories from 1975 to 2015 and prevalence of stunting,underweight and obesity in 2016 among children in Chinese cities:findings from five rounds of a national survey

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World Journal of Pediatrics 2024年第4期20卷 404-412页

作者： Xin‑Nan Zong hui li ya‑Qin Zhang Department of Growth and Development Capital Institute of PediatricsBeijing 100020China

Background A more comprehensive assessment of growth and nutrition in children is required in China due to rapid socioeconomic *** aimed to investigate height and body mass index(BMI)trajectories from 1975 to 2015 and the prevalence of stunting and obesity in 2016 among children in Chinese *** A total of 904,263 children from birth to 6.9 years were collected from a series of nationally representative surveys in *** and BMI trajectories and prevalence of stunting,underweight,overweight and obesity were *** The average height level of Chinese urban children under 7 years presented a positive secular trend from 1975 to 2015;however,a slowing tendency occurred in 2005‒*** apparent increase was observed at the 5th,50th and 95th percentiles of BMI in urban children aged 3 years and older,with a more prominent increase at the 95th *** total prevalence of stunting and underweight under 7 years was 1.4%and 2.0%,*** total prevalence of overweight and obesity under 7 years was 12.6%and 4.3%,respectively,with 12.7%and 4.9%for boys,12.6%and 3.6%for girls,12.1%and 4.0%in urban areas and 13.1%and 4.5%in suburban rural *** The average height level of Chinese urban children has reached World Health Organization child growth standards since 2005 and presented a slowing tendency in secular trend in 2005‒*** attention and efforts and public health interventions should be urgently made to combat overweight and obesity among preschool children.

关键词： Body mass index Children Height Obesity Stunting

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1D silver cluster-assembled materials act as a platform for selectively erasable photoluminescent switch of acetonitrile

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Science China Chemistry 2019年第3期62卷 331-335页

作者： ya-hui li Ren-Wu Huang Peng Luo Man Cao Hong Xu Shuang-Quan Zang Thomas C.W.Mak College of Chemistry and Molecular Engineering Zhengzhou University Department of Chemistry The Chinese University of Hong Kong Shatin

A new 1D silver cluster-assembled complex Ag_(10)bpy-CH_3CN exhibiting intense photoluminescence was reported. Upon the loss of coordinated acetonitrile, Ag_(10)bpy-CH_3CN form Ag_(10)bpy with Ag_(10)S_6 cores slightly distorted, being accompanied with photoluminescence quenching. Inverse process can be realized by treating Ag_(10)bpy with acetonitrile and shows a selectively erasable photoluminescent switch.

关键词： silver cluster photoluminescence switch structure transformation acetonitrile response

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mRNA expression and DNA methylation in three key genes involved in caste differentiation in female honeybees(Apis mellifera)

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Zoological Research 2014年第2期35卷 92-98页

作者： Xin-liang SHAO Shao-Yu HE Xin-Ying ZHUANG Ying FAN ya-hui li Yong-Gang yaO College of Animal Science and Technology Yunnan Agricultural University Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province Kunming Institute of Zoology Eastern Bee Institute Yunnan Agricultural University College of Food Science and Technology Yunnan Agricultural University

In honeybee （Apis mellifera） colonies, queens and workers are altemative forms of the adult female honeybee that develop from genetically identical zygotes but that depend on differential nourishment. Queens and workers display distinct morphologies, anatomies and behavior, better known as caste differentiation. Despite some basic insights, the exact mechanism responsible for this phenomenon, especially at the molecular level, remains unclear although some progress has been achieved. In this study, we examined mRNA levels of the TOR （target of rapamycin） and Dnmt3 （DNA methyltransferase 3） genes, closely related to caste differentiation in honeybees. We also investigated mRNA expression of the S6K （similar to RPS6-p70-protein kinase） gene linked closely to organismal growth and development in queen and worker larvae （1-day and 3-day old）. Last, we investigated the methylation status of these three genes in corresponding castes. We found no difference in mRNA expression for the three genes between 1st instar queen and worker larvae; however, 3rd instar queen larvae had a higher level of TOR mRNA than worker larvae. Methylation levels of all three genes were lower in queen larvae than worker larvae but the differences were not statistically significant. These findings provide basic data for broadening our understanding of caste differentiation in female honeybees.

关键词： Caste differentiation DNA methylation DNA methyltransferase 3 Honeybee Target of rapamycin

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Promoting electrocatalytic nitrogen reduction to ammonia via dopant boron on two-dimensional materials

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Rare Metals 2024年第10期43卷 5117-5125页

作者： ya-hui Cui Wen-Cheng Ouyang Ai-Jun Gao Chang-Yuan Yu li-Peng Zhang State Key Laboratory of Organic-Inorganic Composites College of Chemical EngineeringBeijing University of Chemical Technology College of Materials Science and Engineering Beijing University of Chemical Technology College of life Science and Technology Beijing University of Chemical Technology

Electrocatalytic nitrogen reduction reaction(NRR) is a key process for producing energy efficient and environment friendly ammonia. Boron-doped two-dimensional materials are highly promising as NRR ***, the interaction between doped boron and matrix materials on NRR catalytic performance is still unclear,which is limiting the development of catalysts containing boron for NRR. Here, NRR on different boron-doped twodimensional(2D) materials was explored by first principle theory. It is found that adsorption energy of intermediate*NNH(E*NNH) can be used as a descriptor to characterize the catalytic activity for NRR. Boron-adsorbed black phosphorus(B-BP) is demonstrated showing excellent NRR catalytic activity and suppressing hydrogen evolution reaction. It is disclosed that the excellent catalytic performance of boron-doped structures comes from a proper quantitatively electron transfer(0.8e) between nitrogen in*NNH and the active site boron atom. This work not only established a descriptor for NRR catalytic activity on B-doped 2D materials, but also screened out a potential NRR catalyst. More importantly, the intrinsic reason and mechanism of high catalytic activity of boron-doped structures were proposed. This work provides a design principle for exploring high-performance NRR electrocatalysts containing boron.

关键词： Boron-doped two-dimensional materials Density functional theory Descriptor Electrocatalytic nitrogen reduction reaction

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Apoptosis and necrosis of HeLa cells in response to low-energy ion radiation

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Nuclear Science and Techniques 2006年第4期17卷 222-226页

作者： ZHANG Feng-Qiu ya hui-Yuan li Jing-Yuan PENG Jian-Jun FANG Hua-Sheng SU Ming-Jie QIN Guang-Yong Henan Key Lab of lonbeam Bioengineering Zhengzhou University Zhengzhou 450052 China

The aim of this study was to investigate the damage of low-energy ions to HeLa cells and to particularly examine the relationship between apoptotic and necrotic effects and the low-energy ion radiation. In this study, HeLa cells were irradiated by low-energy ions (30keV N+) at different doses. The level of apoptosis and necrosis was evalu- ated using flow cytometry. Since vacuum is required for experimental low-energy ion generation and irradiation, the cells must be placed in vacuum. Mineral oil was used to prevent dehydration of cells. The results show that the apoptotic rate reached 7.09% when the ion implantation dose was 1 × 1015 ions/cm2; and when the cells were exposed to and implanted at 2 × 1015 ions/cm2 dose, the apoptotic rate was higher than that at 1 × 1015 ions/cm2, and the necrotic rate was 15.63%. In addition, the survival fraction gradually decreased with the increase in implantation dose. Some rela- tionships have been found between the radiation-induced apoptosis and the incubated time after irradiation.

关键词：人宫颈癌传代细胞细胞凋亡细胞增殖低能离子辐射流式细胞测量术

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Thickness dependence of superconductivity in layered GeP_(5)

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Rare Metals 2024年第3期43卷 1323-1328页

作者： lin Wu Ke-Meng yang Wei Gan Rui-Chun Xiao ya-Jie Dai Xi Tang Hong lin hui Han hui li Information Materials and Intelligent Sensing Laboratory of Anhui Province Institute of Physical Science and Information TechnologyAnhui UniversityHefei230601China

Understanding the relationship between dimensionality and superconductivity has attracted substantial research *** this work,we report the effective modulation of superconductivity in GeP_(5)through *** superconducting phase transition temperature improves by~10%as the thickness of GeP_(5)decreases from bulk to~96 nm,behaving as a unique negative relationship between the superconducting phase transition temperatureand thickness.

关键词： superconductivity dimensionality

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Neuroprotective effects of acteoside in a glaucoma mouse model by targeting Serta domain-containing protein 4

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 625-637页

作者： hui-Jie Hao ya-Hong li Bo Yu Xun liu yan Zhang Xiao-li Xing Tianjin Key Laboratory of Retinal Functions and Diseases Tianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin 300384China

AIM:To explore the therapeutic effect and main molecular mechanisms of acteoside in a glaucoma model in DBA/2J ***:Proteomics was used to compare the differentially expressed proteins of C57 and DBA/2J *** acteoside administration in DBA/2J mice,anterior segment observation,intraocular pressure(IOP)monitoring,electrophysiology examination,and hematoxylin and eosin staining were used to analyze any potential ***(IHC)assays were used to verify the proteomics ***,retinal ganglion cell 5(RGC5)cell proliferation was assessed with cell counting kit-8(CCK-8)*** domain-containing protein 4(Sertad4)mRNA and protein expression levels were measured by qRT-PCR and Western blot analysis,***:Proteomics analysis suggested that Sertad4 was the most significantly differentially expressed *** with the saline group,the acteoside treatment group showed decreased IOP,improved N1-P1 wave amplitudes,thicker retina,and larger numbers of cells in the ganglion cell layer(GCL).The IHC results showed that Sertad4 expression levels in DBA/2J mice treated with acteoside were significantly lower than in the saline *** treatment could improve RGC5 cell survival and reduce the Sertad4 mRNA and protein expression levels after glutamate ***:Sertad4 is differentially expressed in DBA/2J *** can protect RGCs from damage,possibly through the downregulation of Sertad4,and has a potential use in glaucoma treatment.

关键词： glaucoma acteoside Serta domaincontaining protein 4 proteomics mice

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Optimal proportioning of iron ore in sintering process based on improved multi-objective beluga whale optimisation algorithm

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Journal of Iron and Steel Research International 2024年第7期31卷 1597-1609页

作者： Zong-ping li Xu-dong li Xue-tong yan Wu Wen Xiao-xin Zeng Rong-jia Zhu ya-hui Wang ling-zhi Yi Zhongye Changtian International Engineering Co. Ltd.Changsha 410205HunanChina College of Automation and Electronic Information Xiangtan UniversityXiangtan 411105HunanChina College of Electrical and Information Engineering Hunan UniversityChangsha 410082HunanChina

Proportioning is an important part of sintering,as it affects the cost of sintering and the quality of sintered *** address the problems posed by the complex raw material information and numerous constraints in the sintering process,a multi-objective optimisation model for sintering proportioning was established,which takes the proportioning cost and TFe as the optimisation ***,an improved multi-objective beluga whale optimisation(IMOBWO)algorithm was proposed to solve the nonlinear,multi-constrained multi-objective optimisation *** algorithm uses the con-strained non-dominance criterion to deal with the constraint problem in the ***,the algorithm employs an opposite learning strategy and a population guidance mechanism based on angular competition and two-population competition strategy to enhance convergence and population *** actual proportioning of a steel plant indicates that the IMOBWO algorithm applied to the ore proportioning process has good convergence and obtains the uniformly distributed Pareto ***,compared with the actual proportioning scheme,the proportioning cost is reduced by 4.3361¥/t,and the TFe content in the mixture is increased by 0.0367%in the optimal compromise ***,the proposed method effectively balances the cost and total iron,facilitating the comprehensive utilisation of sintered iron ore resources while ensuring quality assurance.

关键词： Sintering process Proportioning Iron ore Multi-objective beluga whale optimisation algorithm Proportioning cost

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