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Synthesis of Enriched 10B Boric Acid of Nuclear Grade

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Transactions of Tianjin University 2014年第6期20卷 458-462页

作者： Zhang Lei School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Chemical Engineering Research Center Tianjin UniversityTianjin 300072China

An economic and effective method of preparing enriched 10B boric acid was established by chemical reactionof enriched 10BF3 and CaCO3. A process of boron trifluoride reacting with water was investigated under certainconditions. Calcium carbonate was selected to counteract hydrofluoric acid followed on. Some key operation factorswere investigated, such as temperature, reaction time and the ratio of CaCO3 to 10BF3. The results showed that the yieldof enriched 10B boric acid could reach 97. 2% and the purity was up to 94. 1% under the following conditions： the temperaturewas 50-60,℃, the reaction time was 28 h and the ratio of CaCO3 to 10BF3 was 4. In addition, after recrystallizationand titration analysis, the purity of the product could reach over 99. 2% from 94.1%.

关键词： enriched 10B boric acid boron trifluoride calcium carbonate fluoboric acid hydrogen fluoride

Amelioration of ligamentum flavum hypertrophy using umbilical cord mesenchymal stromal cell-derived extracellular vesicles

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Bioactive Materials 2023年第1期19卷 139-154页

作者： Cheng Ma xin Qi Yi-Fan Wei Zhi Li He-Long Zhang He Li Feng-Lei Yu Ya-Nan Pu Yong-Can Huang Yong-xin ren Department of Orthopaedics The First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu210029China Department of Pathogen Biology and Immunology Nanjing Medical UniversityNanjingJiangsu210029China Department of Orthopaedics Geriatric Hospital of Nanjing Medical UniversityNanjingJiangsu210024China Outpatient&Emergency Management Department The First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu 210029China Shenzhen Engineering Laboratory of Orthopaedic Regenerative Technologies Department of Spine SurgeryPeking University Shenzhen HospitalShenzhen518036China

Ligamentum flavum(LF)hypertrophy(LFH)has been recognised as one of the key contributors to lumbar spinal ***,no effective methods are available to ameliorate this *** this study,human umbilical cord mesenchymal stromal cell-derived extracellular vesicles(hUCMSC-EVs)were introduced for the first time as promising vehicles for drug delivery to treat *** downregulation of miR-146a-5p and miR-221-3p expressions in human LF tissues negatively correlated with increased LF *** hUCMSC-EVs enriched with these two miRNAs significantly suppressed LFH in vivo and notably ameliorated the progression of transforming growth factorβ1(TGF-β1)-induced fibrosis in vitro after delivering these two miRNAs to mouse LF *** results further demonstrated that miR-146a-5p and miR-221-3p directly bonded to the 3′-UTR regions of SMAD4 mRNA,thereby inhibiting the TGF-β/SMAD4 signalling ***,this translational study determined the effectiveness of a hUCMSC-EVs-based approach for the treatment of LFH and revealed the critical target of miR-146a-5p and *** findings provide new insights into promising therapeutics using a hUCMSC-EVs-based delivery system for patients with lumbar spinal stenosis.

关键词： Ligamentum flavum hypertrophy Fibrosis Umbilical cord mesenchymal stromal cells Extracellular vesicle miR-146a-5p miR-221-3p

Fixed point theorems for better admissible multimaps on Abstract convex spaces

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Applied Mathematics(A Journal of Chinese Universities) 2010年第1期25卷 55-62页

作者： LIU Xue-wen ZHANG Yue TAN ren-xin School of Mathematics and Computer Science, Chongqing Normal University, Chongqing 400047, China School of Mathematics and Computer Science Chongqing Normal University Chongqing China

In this paper, a better admissible class B＋ is introduced and a new fixed point theorem for better admissible multimap is proved on abstract convex spaces. As a consequence, we deduce a new fixed point theorem on abs... 详细信息

关键词： Multimap fixed point abstract convex space better admissible class.

Ankfy1 is dispensable for neural stem/precursor cell development

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Neural Regeneration Research 2016年第11期11卷 1804-1809页

作者： Chao Weng Man Ding Lian-sheng Chang Ming-xin ren Hong-feng Zhang Zu-neng Lu Hui Fu Department of Neurology Renmin Hospital of Wuhan University Department of Anatomy and Embryology School of Basic Medical SciencesWuhan University Department of Pathology Central Hospital of Wuhan Hubei-MOST KLOS & KLOBME

There are few studies on the membrane protein Ankfyl. We have found Ankfyl is specifically expressed in neural stem/precursor cells during early development in mice （murine）. To further explore Ankfyl function in neural development, we developed a gene knockout mouse with a mixed Balb/C and C57/BL6 genetic background. Using immunofluorescence and in situ hybridization, neural defects were absent in mixed genetic Ankfyl null mice during development and in adults up to 2 months old. However, Ankfyl gene knockout mice with a pure genetic background were found to be lethal in the C57/BL6 inbred mice embryos, even after seven generations of backcrossing. Polymerase chain reaction confirmed homozygotes were unattainable as early as embryonic day 11.5. We conclude that Ankfyl protein is dispensable in neural stem/precursor ceils, but could be critical for early embryonic murine development, depending on the genetic background.

关键词： nerve regeneration Ankfyl neural development genetic background protein function gene knockout neural stem/precursor cells embryo neural regeneration

Gravitational Deformation Measurement Method for the Main Reflector and Sub-reflector of the 70 m Antenna by Laser Scanner

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Research in Astronomy and Astrophysics 2022年第9期22卷 1-9页

作者： Lian-Bo Fu Jian-Jun Liu Wei Yan De-Qing Kong xin ren Chen-Di Liu Hong-Bo Zhang Key Laboratory of Lunar and Dep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBejing 100101China Urunaivreyr of Chinese Academy of Sciences Beijing 100049China

Large antennas play an important role in deep space exploration and astronomical research. However, their performances are inevitably affected by the main reflector surface deformation and sub-reflector displacement resulting from the factors of wind, temperature, and gravity, among which the effect of gravity is especially pronounced. In this work, a three-dimensional laser scanner was employed to measure the main reflector and subreflector gravitational deformation of the Tianjin 70 m antenna at different elevation angles. Here, we solved the antenna main reflector deformation and sub-reflector displacement, and analyzed the deformation law of the antenna under the action of gravity. A new measurement method of antenna main reflector deformation and subreflector displacement is realized by mutual verification of the measured results and theoretical simulations. This method will help to improve the antenna performance and provide a reference to optimize the design of largeaperture antennas.

关键词： telescopes techniques:radar astronomy planets and satellites:detection

An Anterior Cingulate Cortex-to-Midbrain Projection Controls Chronic Itch in

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Neuroscience Bulletin 2023年第5期39卷 793-807页

作者： Ting-Ting Zhang Su-Shan Guo Hui-Ying Wang Qi Jing xin Yi Zi-Han Hu xin-ren Yu Tian-Le Xu Ming-Gang Liu Xuan Zhao Department of Anesthesiology Shanghai Tenth People's HospitalSchool of MedicineTongji UniversityShanghai 200072China Department of Anatomy and Physiology Shanghai Jiao Tong University School of MedicineShanghai 200025China Center for Brain Science of Shanghai Children's Medical Center Shanghai Jiao Tong University School of MedicineShanghai 200127China

Itch is an unpleasant sensation that provokes the desire to *** acute itch serves as a protec-tive system to warn the body of external irritating agents,chronic itch is a debilitating but poorly-treated clinical dis-ease leading to repetitive scratching and skin ***-ever,the neural mechanisms underlying the pathophysiol-ogy of chronic itch remain ***,we identified a cell type-dependent role of the anterior cingulate cortex(ACC)in controlling chronic itch-related excessive scratch-ing behaviors in ***,we delineated a neural circuit originating from excitatory neurons of the ACC to the ventral tegmental area(VTA)that was critically involved in chronic ***,we demonstrate that the ACC→VTA circuit also selectively modulated histaminergic acute ***,the ACC neurons were shown to predomi-nantly innervate the non-dopaminergic neurons of the *** together,our findings uncover a cortex-midbrain cir-cuit for chronic itch-evoked scratching behaviors and shed novel insights on therapeutic intervention.

关键词： sAnterior cingulate cortex Chronic itch Ventral tegmental area-Chemogenetics Neural circuit

Application of the catastrophe progression method in predicting coal and gas outburst

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Mining Science and Technology 2009年第4期19卷 430-434页

作者： ZHANG Tian-jun ren Shu-xin LI Shu-gang ZHANG Tian-cai XU Hong-jie College of Science Xi＇ an University of Science and Technology Xi＇an Shaanxi 710054 China Energy Institute Xi＇an University of Science and Technology Xi＇an Shaanxi 710054 China xinjiang Times Petroleum Engineering Corporation Karamay Xinjiang 834000 China

Based on catastrophe theory,we used the catastrophe progression method to predict the risk of coal and gas outbursts in coal *** to the major factors affecting coal and gas outbursts,we built a comprehensive evaluation index system and a coal and gas outburst prediction *** addition,we performed a standard transformation for each index system;based on the degree the various indices affect the risk of an outburst,to make the data *** on the outburst data from eight mines,we determined catastrophe progression values and verified these *** results show that:1) converting multi-dimensional problems into one-dimensional problems using this catastrophe progression method can simplify the steps of predicting coal and gas outbursts;2) when pre-determined catastrophe progression values are used to predict coal and gas outbursts,the predicting accuracy rate can be as high as 87.5%;3) the various coal mines have different factors inducing outbursts with varying importance of these factors and 4) the catastrophe progression values,calculated based on these factors,can be used effectively to predict the risk of outbursts in coal mines.

关键词： standard transformation catastrophe progression method coal and gas outburst

The optical/UV excess of X-ray-dim isolated neutron star Ⅱ.Nonuniformity of plasma on a strangeon star surface

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Research in Astronomy and Astrophysics 2018年第7期18卷 81-92页

作者： Wei-Yang Wang Yi Feng Xiao-Yu Lai Yun-Yang Li Ji-Guang Lu Xuelei Chen ren-xin Xu Key Laboratory of Computational Astrophysics National Astronomical ObservatoriesChinese Academy ofSciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Hubei University of Education Wuhan 430205China Key Laboratory of Radio Astronomy Chinese Academy of SciencesBeijing 100101China Center for High Energy Physics Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

Several X-ray-dim isolated neutron stars （XDINSs）, also known as the Magnificent Seven, exhibit a Planck-like soft X-ray spectrum. In the optical/ultraviolet （UV） band, there is an excess of radiation compared to an extrapolation from the X-ray spectrum. However, the majority exhibits ＂spec- tral deviations＂： the fact that there is more flux at longer wavelengths makes spectra deviate from the Rayleigh-Jeans law. A model of bremsstrahlung emission from a nonuniform plasma atmosphere is proposed in the regime of a strangeon star to explain the optical/UV excess and its spectral devi- ation as well as X-ray pulsation. The atmosphere is on the surface of strangeon matter, which has negligible emission, and is formed by the accretion of ISM-fed debris disk matter moving along the magnetic field lines to near the polar caps. These particles may spread out of the polar regions which makes the atmosphere non-uniform. The modeled electron temperatures are ~ 100 - 200 eV with radi- ation radii Ropt ~ 5 - 14km. The spectra of five sources （RX J0720.4-3125, RX J0806.4-4123, RX J1308.6＋2127, RX J1605.3＋3249, RX J1856.5-3754） from optical/UV to X-ray bands can be fitted well by the radiative model, and exhibit Gaussian absorption lines at ~ 100 - 500 eV as would be expected. Furthermore, the surroundings （i.e., fallback disks or dusty belts） of XDINSs could be tested by future infrared/submillimeter observations.

关键词： X-rays stars - stars neutron - stars individual

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中外环境标志的比较

中国环境科学 1999年第2期19卷 189-192页

作者：任欣中国环境科学研究院管理所北京100012

对我国及发达国家的环境标志，在产品的遴选，标志产品的认证．标准的制订和标志产品的市场效果等方面进行比较：从供需角度分析我国环境标志取得的成绩，存在的问题及其原因；对照国外的经验，就如何完善我国的环境标志，如何使其与环... 详细信息

对我国及发达国家的环境标志，在产品的遴选，标志产品的认证．标准的制订和标志产品的市场效果等方面进行比较：从供需角度分析我国环境标志取得的成绩，存在的问题及其原因；对照国外的经验，就如何完善我国的环境标志，如何使其与环境管理体系和清洁生产审计相协调，共同促进可持续发展提出了建议。

关键词：环境标志清洁生产环境管理体系中国国外