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Significantly enhanced performance and conductivity mechanism in Nb/Mn co-doped CaBi_(4)Ti_(4)O_(15)ferroelectrics

Journal of Materiomics 2024年第3期10卷 652-669页

作者： Jiageng Xu Shaoxiong Xie qian Xu jie Xing Qingyuan Wang Jianguo Zhu School of Aeronautics and Astronautics Sichuan UniversityChengdu610000China Institute for Advanced Study Chengdu UniversityChengdu610106China Department of Mechanical Engineering Kyushu UniversityFukuoka819-0395Japan College of Architecture and Environment Sichuan UniversityChengdu610065China College of Material Science and Engineering Sichuan UniversityChengdu610065China

With the rapid development of high-end industries,the demand for high-temperature piezoelectric materials is significantly ***,realizing the ultra-high performance to meet more ap-plications still faces major scientific and engineering challenges of our ***,a new Nb/Mn co-doped CaBi_(4)Ti_(4)O_(15)(CBT)high-temperature piezoelectric material system of CaBi_(4)Ti_(4-x)(Nb_(2/3)Mn_(1/3))_(x)O_(15)was synthesized by the conventional solid-state sintering *** results show that the addition of the dopants tends to break the long-range ferroelectric chain and soften the flexibility of polarization,resulting in more distorted crystal structure and better ferroelectric properties of CBT *** ultra-high piezoelectric constant(d_(33)=26.8 pC/N)is thus attained in CBT-based ceramics with x=0.12,which is about several times larger than that of pure CBT ***,numerous nano-sized layered domain structures that lie on the lateral plane of grains are observed in ceramics,with lower domain wall energy and better dynamic features under electric fields,mainly responsible for the origin of enhanced ***,excess dopants could make the conductivity mechanism of CBT ceramics transform from p-type to n-type,and also result in a shift of conduction relaxation mechanism from defect dipole rotation polarization to electron relaxation *** work not only provides a promising candidate for high-temperature piezoelectric materials,but also opens a window for opti-mizing performance by tailoring domain structures using chemical modification.

关键词： CaBi_(4)Ti_(4)O_(15) Lattice distortion Electrical performance Domain structure Conductivity mechanism

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混凝沉淀-气浮-间歇曝气MBR组合工艺处理餐厨发酵沼液的研究

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四川环境 2024年第1期43卷 181-185页

作者：张翠翠史文悦钱伟杰黄连芝郑炜浙江双益环保科技发展有限公司浙江嘉兴314000 浙江清华长三角研究院浙江嘉兴314000

为解决餐厨垃圾厌氧发酵沼液处理的难题,研究采用混凝沉淀-气浮-间歇曝气MBR组合工艺对餐厨垃圾发酵沼液进行处理。结果表明,经混凝沉淀-气浮预处理,COD、TP、SS、动植物油去除效率分别达到85.3%,98.7%,99.4%和99.4%;氨氮和总氮的去除... 详细信息

为解决餐厨垃圾厌氧发酵沼液处理的难题,研究采用混凝沉淀-气浮-间歇曝气MBR组合工艺对餐厨垃圾发酵沼液进行处理。结果表明,经混凝沉淀-气浮预处理,COD、TP、SS、动植物油去除效率分别达到85.3%,98.7%,99.4%和99.4%;氨氮和总氮的去除效果较差,去除率分别为49.96%和52.63%。进一步考察了间歇曝气MBR在不同C/N比下对COD、氨氮和总氮的去除效果,综合考虑工艺运行的技术经济合理性,C/N比为3为最优运行条件,COD、氨氮和TN的去除率分别为87.63%、98.40%和96.67%。经混凝沉淀-气浮-间歇曝气MBR组合工艺处理,出水水质满足《污水综合排放标准》(GB8978-1996)中的三级排放标准。

关键词：间歇曝气 MBR 脱氮低C/N比

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电缆电气参数不同计算方法及其比较

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高电压技术 2013年第3期39卷 689-697页

作者：徐政钱洁浙江大学电气工程学院杭州310027

为了能够准确、方便地计算出电力电缆的电气参数,包括电缆的电阻矩阵、电感矩阵、电容矩阵、电导矩阵以及序阻抗等,分别采用Carson-Clem公式、《电力系统建模及故障分析》中的方法以及Matlab中power_cableparam功能所用的方法进行比较,... 详细信息

为了能够准确、方便地计算出电力电缆的电气参数,包括电缆的电阻矩阵、电感矩阵、电容矩阵、电导矩阵以及序阻抗等,分别采用Carson-Clem公式、《电力系统建模及故障分析》中的方法以及Matlab中power_cableparam功能所用的方法进行比较,研究它们针对不同结构和不同排列方式的电缆的计算原理,并给出正序模型和零序模型中相关参数的计算方法,再以不同结构的电缆为算例验证其准确性。比较结果显示,《电力系统建模及故障分析》中的方法在计算线芯和护套间电容时存在缺陷;power_cableparam功能所用的方法计算导体自身电阻时所用的是直流电阻,未考虑集肤效应和邻近效应,且只可用于计算相互等间距的电缆,对于非等间距排列电缆和带铠装电缆不适用。结果说明Carson-Clem公式在准确性和通用性方面是最优的,采用此方法可以为电缆的后续研究提供准确、可靠的电缆参数。

关键词：电力电缆电气参数电阻矩阵电感矩阵电容矩阵序阻抗

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Increased N6-methyladenosine is related to the promotion of the methyltransferase METTL14 in ovarian aging

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Genes & Diseases 2024年第3期11卷 151-154页

作者： Chunfeng qian Zhenxing Liu Yonghong qian jie Ding Rulei Chen Han Su Minghong Shen Hong Li Boxian Huang State Key Laboratory of Reproductive Medicine and Offspring Health Suzhou Affliated Hospital of Nanjing Medicine and Offspring HealthSuzhou Affiliated Hospital of Nanjing Medical UniversitySuzhouMunicipal HospitalGusu SchoolNanjing Medical UniversitySuzhouJiangsu 215002China Department of Gynecology Affliated Suzhou Hospital of Nanjing Medical UniversitySuzhou Municipal HospitalGusu School of Nanjing Medical UniversitySuzhouJiangsu 215002China Department of Pathology Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhou Municipal HospitalGusu School of Nanjing Medical UniversitySuzhouJiangsu 215002China

The ovary is a vital female reproductive organ that functions to produce oocyte gametes and cyclically expressed sex hormones to maintain reproductive capacity and hormone *** aging,characterized by declines in follicle quantity and oocyte quality,leads to premature ovarian failure,premature ovarian insufficiency,or diminished ovarian reserve,thus contributing to female *** gene-expression signatures from RNA transcriptional level and post-transcriptional regulation are relative to oocyte quality and reproductive age.

关键词： promotion signature maintain

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Pb Surfactant-Assisted Co Film Growth on Cu (111)

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Chinese Physics Letters 2000年第8期17卷 595-597页

作者： XU Ming-Chun qian Hai-jie Liu Feng-qin KRASH Ibrahim LAI Wu-Yan WU Si-Cheng State Key Laboratory of Magnetism Center for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100080 Synchrotron Radiation Laboratory Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100039 Department of Physics Peking UniversityBeijing 100871

Surfactant-assisted Co film epitaxy growth on Cu(111)using Pb as a surfactant was studied by means of Auger electron spectra and synchrotron radiation photoemission *** results reveal that with increasing the Co thickness most of the Pb atoms always float on the *** with 0.7ML(monolayer)Pb,the Co film with 1.5 ML Pb surfactant has more layer-by-layer growth on Cu(111).The predeposited Pb layer can suppress the intralayer diffusion on the Cu(111)surface and effectively increase the Co island density at the initial stage of Co *** the contrary,a Pb-Co surface alloy was found during the Co film growth;this may hinder the interlayer diffusion of the deposited Co atoms,which is unfavorable to the layer-by-layer *** Pb-Co is also considered to be the main reason why some Pb atoms have been buried in the Co films.

关键词： Cu(111) alloy surfactant

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Surface Alloying of Submonolayer Pb on Cu(111) Studied by Photoemission

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Chinese Physics Letters 2000年第1期17卷 49-51页

作者： XU Ming-Chun qian Hai-jie LIU Feng-Qin KRASH Ibrahim LAI Wu-Yan WU Si-Cheng State Key Laboratory of Magnetics Center for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100080 Synchrotron Radiation Laboratory Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100039 Department of Physics Peking UniversityBeijing 100871

The reactions of superthin Pb Hlms on a Cu(111)surface with respect to the coverage of Pb and annealing have been studied by synchrotron radiation *** submonolayer Pb atoms deposited at room temperature are distributed on the Cu(111)surface as two-dimensional(2D)*** to 200℃ gives rise to Pb-Cu surface alloy *** show that the surface alloy occurs only in the first layer of the Cu(111)*** a surfactant,Pb can promote 2D layer-by-layer growth of thin Hlms on Cu(111),but the Pb~Cu surface alloying may have an unfavorable effect on the activation process.

关键词： Cu(111) alloy alloying

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Development of RPA-Cas12a-fluorescence assay for rapid and reliable detection of human bocavirus 1

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Animal Models and Experimental Medicine 2024年第2期7卷 179-188页

作者： Weidong qian Xuefei Wang Ting Wang jie Huang qian Zhang Yongdong Li Si Chen School of Food and Biological Engineering Shaanxi University of Science and TechnologyXi'anP.R.China Department of Dermatology Huazhong University of Science and Technology Union Shenzhen HospitalShenzhenP.R.China Ningbo Municipal Center for Disease Control and Prevention NingboP.R.China Medical College of Shenzhen University ShenzhenP.R.China

Human bocavirus(HBoV)1 is considered an important pathogen that mainly affects infants aged 6–24 months,but preventing viral transmission in resource-limited regions through rapid and affordable on-site diagnosis of individuals with early infection of HBoV1 remains somewhat ***,we present a novel faster,lower cost,reliable method for the detection of HBoV1,which integrates a recombinase polymerase amplification(RPA)assay with the CRISPR/Cas12a system,designated the RPA-Cas12a-fluorescence *** RPA-Cas12a-fluorescence system can specifically detect target gene levels as low as 0.5 copies of HBoV1 plasmid DNA per microliter within 40 min at 37℃without the need for sophisticated *** method also demonstrates excellent specificity without cross-reactivity to non-target ***,the method was appraised using 28 clinical samples,and displayed high accuracy with positive and negative predictive agreement of 90.9%and 100%,***,our proposed rapid and sensitive HBoV1 detection method,the RPA-Cas12a-fluorescence assay,shows promising potential for early on-site diagnosis of HBoV1 infection in the fields of public health and health *** established RPA-Cas12a-fluorescence assay is rapid and reliable method for human bocavirus 1 *** RPA-Cas12a-fluorescence assay can be completed within 40 min with robust specificity and sensitivity of 0.5 copies/μl.

关键词： CRISPR-Cas12a detection human bocavirus 1 on-site diagnosis recombinase polymerase amplification

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Homoharringtonine in combination with cytarabine and aclarubicin as induction therapy improves remission and survival of patients with higher risk myelodysplastic syndromes

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Chinese Medical Journal 2010年第1期123卷 108-110页

作者： XU Wei-lai JIN jie qian Wen-bin Institute of Hematology First Affiliated Hospital of College ofMedicine Zhejiang University Hangzhou Zhejiang 310003China

Myelodysplastic syndromes （MDS） are a heterogeneous group of clonal disorderscharacterized by ineffective hematopoiesis; they manifest clinically as anemia, neutropenia, and thrombocytopenia.1＇2 Higher risk MDS include patients in the intermediate-2 and high-risk categories of the International Prognostic Scoring System （IPSS）, as well as patients with MDS secondary to radiation or chemical exposure.3 The patients with higher risk MDS have a peculiar propensity to evolve into acute myeloid leukemia （AML）, and have a median survival of 〈12 months.4 Management of higher risk MDS varies from supportive care with transfusions or hematopoietic cytokines to high-intensity3 chemotherapy or hematopoietic stem cell transplantation. The impact of intensive myelosuppressive chemotherapy, similar to AML induction therapy, has been investigated. The results are comparable to the reported outcome of patients with AML, i.e. complete remission （CR） rates of 40%-60% and median overall survival （OS） of 8-12 months,s Thus, innovative approaches are needed for the treatment of higher risk MDS.

关键词： myelodysplastic syndromes high-intensity chemotherapy induction homoharringtonine

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Invasive versus conservative strategy in consecutive patients aged 80 years or older with non-ST-segment elevation myocardial infarction: a retrospective study in China

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Journal of Geriatric Cardiology 2019年第10期16卷 741-748页

作者： Yong-Gang SUI Si-Yong TENG jie qian Yuan WU Ke-Fei DOU Yi-Da TANG Shu-Bin QIAO Yong-Jian WU Department of Cardiology Fuwai Hospital National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College

Objective To investigate whether the very elderly patients with non-ST-segment elevation myocardial infarction (NSTEMI) will benefit from an invasive strategy versus a conservative strategy. Methods 190 consecutive patients aged 80 years or older with NSTEMI were included in the retrospective study from September 2014 to August 2017, of which 69 patients received conservative strategy and 121 patients received invasive strategy. The primary outcome was death. Multivariate Cox regression models were used to assess the statistical association between strategies and mortality. The survival probability was further analyzed. Results The primary outcome occurred in 17.4% patients in the invasive group and in 42.0% patients in the conservative group (P = 0.0002). The readmission rate in the invasive group (14.9%) was higher than that in the conservative group (7.2%). Creatinine level (OR = 1.01, 95% CI: 0.10–1.03, P = 0.05) and use of diuretic (OR = 3.65, 95% CI: 1.56–8.53, P = 0.003) were independent influential factors for invasive strategy. HRs for multivariate Cox regression models were 3.45 (95% CI: 1.77–6.75, P = 0.0003), 3.02 (95% CI: 1.52–6.01, P = 0.0017), 2.93 (95% CI: 1. 46–5.86, P = 0.0024) and 2.47 (95% CI: 1.20–5.07, P = 0.0137). Compared with the patients received invasive strategy, the conservative group had remarkably reduced survival probability with time since treatment (P < 0.001). Conclusions An invasive strategy is superior to a conservative strategy in reducing mortality of patients aged 80 years or older with NSTEMI. Our results suggest that an invasive strategy is more suitable for the very elderly patients with NSTEMI in China.

关键词： Conservative strategy Death Invasive strategy Non-ST-segment elevation myocardial infarction

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Experimental study on wax deposition of highly paraffinic oil in intermittent gas-oil flow in pipelines

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Petroleum Science 2024年第3期21卷 2080-2088页

作者： Chuan-Shuo Wang qian-Li Ma Xiao-Fang Lv jie Zhang Yang Liu Shi-Dong Zhou Jiangsu Key Laboratory of Oil and Gas Storage and Transportation Technology Changzhou UniversityChangzhou213164JiangsuPR China Hade Oil and Gas Development Department Tarim Oilfield BranchKorla841000XinjiangPR China

Oil-gas two phase wax deposition is a fairly common and open-ended question in flow assurance of multiphase transportation *** paper investigated the two main aspects of oil-gas two phase wax deposition layer:apparent thickness and crystal structure characteristics.A typical highly paraffinic oil in Bohai Sea,China,was used as the experimental material to investigate the wax deposition thickness in oil-gas two phase under the influence of different oil temperatures,superficial gas/liquid phase velocities and gas-oil ratios by using multiphase flow loop experimental *** as in the classical theory of wax molecular diffusion,it showed that wax deposition thickness of oil-gas two phase increased with increasing oil *** of the impact of different superficial phase velocities found that the actual liquid flow heat transfer and shear stripping was the gas phase dominant mechanisms determining wax deposit *** addition,the crystal structure of the wax deposition layer was characterized with the help of small-angle X-ray scattering(SAXS)for different circumferential positions,flow rates and gas-oil *** bottom deposition layer had a complex crystal structure and high hardness,which were subject to change over flow rate ***,the SAXS results provided evidence that the indirect effect of the actual liquid velocity modified by the gas phase was the main *** study of the effect of gas phase on the wax deposition of oil-gas two phase will help shed light onto the mechanism by which this important process *** findings address a very urgent need in the field of wax deposition of highly paraffinic oil to understand the flow security of oilgas two phase that occurs easily in multiphase field pipelines.

关键词： Oil-gas two phase Highly paraffinic oil Wax deposition SAXS

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