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Hydrocracking diversity in n-dodecane isomerization on Pt/ZSM-22 and Pt/ZSM-23 catalysts and their catalytic performance for hydrodewaxing of lube base oil

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Petroleum Science 2020年第6期17卷 1752-1763页

作者： Shan-Bin Gao Zhen Zhao Xue-Feng Lu Ke-Bin Chi Ai-Jun Duan Yan-Feng Liu Xiang-Bin Meng Ming-Wei Tan hong-yue yu yu-Ge Shen Meng-Chen Li State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Petrochemical Research Institute PetroChina Company LimitedBeijing 100195China

Nobel metallic Pt/ZSM-22 and Pt/ZSM-23 catalysts were prepared for hydroisomerization of normal dodecane and hydrodewaxing of heavy waxy lube base *** hydroisomerization performance of n-dodecane indicated that the Pt/ZSM-23 catalyst preferred to crack the C-C bond near the middle of n-dodecane chain,while the Pt/ZSM-22 catalyst was favorable for breaking the carbon chain near the end of *** a result,more than 2%of light products(gas plus naphtha)and3%more of heavy lube base oil with low-pour point and high viscosity index were produced on Pt/ZSM-22 than those on Pt/ZSM-23 while using the heavy waxy vacuum distillate oil as feedstock.

关键词： Isomerization Hydrocracking Catalysts Pt/ZSM-22 Pt/ZSM-23 Dodecane Lube base oil

Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan Guo hong-Bo Jin Cong-Feng Qiao yue-Liang Wu The International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical Sciences University of Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries

Monitoring the source of mesenchymal stem cells in patients after transplantation of mismatched-sex hematopoietic stem cells plus thirdparty cells

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Chinese Medical Journal 2013年第22期126卷 4254-4259页

作者： WANG Jing HUANG Xiao-jun XU Lan-ping LIU Dai-hong CHEN Huan CHEN yu-hong LAI yue-yun HOU Rui-qin QIN Xiao-ying LIU Kai-yan Peking University Institute of Hematology Peking University People's Hospital Beijing 100044 China

Background In bone marrow transplant patients, the microenvironment in bone marrow is damaged after chemotherapy or radiotherapy. Subsequent to allogenic hematopoietic stem cell transplantation in patients with clinically successful engraftments, the source of mesenchymal stem cells （MSCs） remains controversial. To further verify the stimulatory effect of the simultaneous transplantation of cells from second donors on engraftment success for hematopoietic stem cell transplantation in support of donor MSCs engraftments, the aim of this study is to monitor the dynamics of the engraftment of bone marrow-derived MSCs in patients after transplantation with mismatched-sex hematopoietic stem and third-party cells. Methods In this study, the hematopoietic stem cells from 32 clinical donors of different sexes that resulted in successful engraftments were selected for transplantation and were classified into three groups for research purposes： group A consisted of 14 cases of transplantation with bone marrow and recruited peripheral hematopoietic stem cell transplantation, group B contained 8 cases of simultaneous re-transfusion of MSCs from the second donor, and group C contained 10 cases of simultaneous re-transfusion of umbilical blood from the second donor. The bone marrow from 32 patients with successful engraftments of hematopoietic transplantation were selected and sub-cultured with MSCs. Flow cytometry （FCM） was used to measure the expression of surface antigens on MSCs. Denaturing high-performance liquid chromatography （DHPLC） in combination with polymerase chain reaction amplification of short tandem repeats （STR- PCR） was used to measure the engraftment status of fifth-generation MSCs in patients. Fluorescence in situ hybridization （FISH） revealed the sex origin of the fifth-generation MSCs in 32 patients. Dynamic examinations were performed on patients receiving donor transplantations. Results The progenies of fifth-generation MSCs were successfully cultured in 32

关键词： hematopoietic stem cell transplantation mesenchymal stem cells source of engraftment

金合金全冠和镍铬合金全冠对牙周组织影响的比较

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中国医学科学院学报 2010年第3期32卷 269-271页

作者：胡运东吴效民于宏跃马天岳中国医学科学院北京协和医学院北京协和医院口腔科北京100730

目的比较金合金全冠和镍铬合金全冠对基牙牙周组织的影响。方法将20例需做一颗患牙全冠修复的患者分为金合金全冠组(n=9)和镍铬合金全冠组(n=11)两组,并以每颗实验牙的健康对侧同名牙作为对照牙,分别于基牙预备前及修复6个月后测定实验... 详细信息

目的比较金合金全冠和镍铬合金全冠对基牙牙周组织的影响。方法将20例需做一颗患牙全冠修复的患者分为金合金全冠组(n=9)和镍铬合金全冠组(n=11)两组,并以每颗实验牙的健康对侧同名牙作为对照牙,分别于基牙预备前及修复6个月后测定实验牙及其对照牙的龈沟液量、探诊深度及龈沟出血指数。结果金合金全冠组实验牙基牙预备前的龈沟液量明显大于修复6个月后(P0.05)。结论修复后短期内未观察到金合金全冠对基牙牙周组织造成明显损害,而镍铬合金全冠则使基牙的龈沟出血指数增大。

关键词：金合金全冠镍铬合金金属全冠牙周组织

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基于SVD-DWT域数字图像水印算法

计算机仿真 2009年第8期26卷 104-107页

作者：钱华明于鸿越哈尔滨工程大学自动化学院黑龙江哈尔滨150001

在一类基于奇异值分解(SVD)的数字水印算法中,提取过程要使用原始图像奇异值分解的正交矩阵;若用其它图像的正交矩阵来代替,则可以重构出任意期望的水印图像,表明算法具有非常高的虚警率。为了消除算法的不确定性,提出了一种改进的基于S... 详细信息

在一类基于奇异值分解(SVD)的数字水印算法中,提取过程要使用原始图像奇异值分解的正交矩阵;若用其它图像的正交矩阵来代替,则可以重构出任意期望的水印图像,表明算法具有非常高的虚警率。为了消除算法的不确定性,提出了一种改进的基于SVD-DWT域的数字图像水印算法,将SVD分解的正交矩阵U作为控制参数嵌入载体图像小波分解的细节子带中。实验结果表明,该算法既保持了原有算法的鲁棒性和不可见性,同时也消除了提取结果的不确定性。因此可以将算法应用于版权保护。

关键词：数字水印奇异值分解虚警率离散小波分解

Effect of acupuncture on menopausal hot flashes:Study protocol for a randomized controlled clinical trial

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World Journal of Acupuncture-Moxibustion 2021年第4期31卷 324-329页

作者： Kun XU Anna Bogachko(Sweden) Shan-shan LI Xuan YIN hong-yu yue Tian LI Li-xing LAO Shi-fen XU Shanghai Municipal Hospital of Traditional Chinese Medicine Shanghai University of Traditional Chinese MedicineShanghai 200071China Virginia University of Integrative Medicine FairfaxVirginia 22031United Stares

Background:Hot flashes are one of the most common symptoms in menopause and significantly affect the quality of life of 67% of menopausal *** is found to be a low risk treatment in treating hot flashes but the evidence for its effectiveness is *** developed an optimized acupuncture treatment protocol and designed a randomized controlled trial(RCT) to assess the efficacy of acupuncture for reducing hot flashes in menopausal ***:This is a single-site,single-blind,randomized sham-controlled trial with two parallel arms.A total of 60 eligible patients will be recruited and randomly assigned to either the acupuncture group(n=30) or the sham acupuncture group(n=30).Treatment will be given twice a week,for 30 min,for six consecutive *** primary outcome is the hot flashes scores,assessed using the validated hot flashes diary at baseline,week 3,week 6 and week *** secondary outcome will be measured by menopause-specific quality of life(MENQOL) at baseline,week 6,and week ***,any adverse events will be ***:If the outcome of this study confirms acupuncture to be an effective therapy to reduce hot flashes in menopausal women,we expect this study to inspire further investigations and provide useful information in forming an optimal acupuncture treatment protocol for *** registration:Chinese Clinical Trial Registry identifier:ChiCTR1800018638,Date of registration:30 th September ***:http://***/***?proj=31462.

关键词： Hot flashes Menopause Acupuncture Randamized controlled trial(RCT)

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钙盐处理对真丝纤维力学性能的影响

丝绸 2003年第12期40卷 33-35页

作者：林红陈宇岳苏州大学材料工程学院江苏苏州215021

测定了硝酸钙溶液处理后真丝纤维的力学性能,比较并研究了处理温度对丝纤维性能的影响。结果发现,真丝纤维经硝酸钙溶液处理后,产生重量损失,丝纤维的断裂强度下降,这一趋势并随着处理温度的提高、处理时间的延长更加明显。

关键词：真丝纤维力学性能温度硝酸钙溶液处理重量损失断裂强度

DB11/T828.3-2011中12号染色体标记筛选及适用性评价研究

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中国比较医学杂志 2017年第7期27卷 59-63页

作者：魏杰王洪于鹏丽岳秉飞中国食品药品检定研究院北京100050

目的对北京小型猪遗传质量控制地方标准DB11/T828.3-2011中空缺的12号染色体标记进行筛选,并通过比较不同标记对同种群的遗传评价对地标的适用性进行分析。方法结合文献报道,选取12号染色体上的4对微卫星标记,利用2个中国农大小型猪群... 详细信息

目的对北京小型猪遗传质量控制地方标准DB11/T828.3-2011中空缺的12号染色体标记进行筛选,并通过比较不同标记对同种群的遗传评价对地标的适用性进行分析。方法结合文献报道,选取12号染色体上的4对微卫星标记,利用2个中国农大小型猪群体进行筛选;选取高度多态的12号染色体标记合并标准方法的18对染色体标记,形成全染色体法,通过不同方法对同批次群体的遗传质量评价进行比较分析。所得结果均使用Popgen32软件处理分析。结果筛选到的4对12号染色体标记PIC值均大于0.5,为高度多态;现行标准在染色体覆盖率、扩增稳定性、结果评价三项指标结果分别为94.7%、96.0%、农大I系不合格而农大III系合格,增加12号染色体后评价的三项指标的结果分别为100%、96.6%和两群体均合格。结论本研究筛选的4对12号染色体标记具有高度多态性,为完善DB11/T828.3-2011提供数据支撑。

关键词： DB11/T828.3-2011 12号染色体多态性适用性遗传质量

CMIP5耦合模式对欧亚大陆冬季雪水当量的模拟及预估

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气候与环境研究 2017年第3期22卷 253-270页

作者：杨笑宇林朝晖王雨曦陈红俞越中国科学院大气物理研究所国际气候与环境科学中心北京100029 中国科学院大学北京100049 南京信息工程大学气象灾害预报预警与评估协同创新中心南京210044

基于美国冰雪资料中心(NSIDC)提供的卫星遥感雪水当量资料,评估了26个CMIP5(Coupled Model Inter-comparison Project)耦合模式对1981~2005年欧亚大陆冬季雪水当量的模拟能力,在此基础上应用多模式集合平均结果,预估了21世纪欧亚大陆雪... 详细信息

基于美国冰雪资料中心(NSIDC)提供的卫星遥感雪水当量资料,评估了26个CMIP5(Coupled Model Inter-comparison Project)耦合模式对1981~2005年欧亚大陆冬季雪水当量的模拟能力,在此基础上应用多模式集合平均结果,预估了21世纪欧亚大陆雪水当量的变化情况。结果表明,CMIP5耦合模式对欧亚大陆冬季雪水当量空间分布具有一定的模拟能力,能够再现出欧亚大陆冬季雪水当量由南向北递增、青藏高原积雪多于同纬度其他地区的特征;就雪水当量的幅值而言,几乎所有模式均显著低估了西伯利亚中部雪水当量的大值中心,对中国东北地区雪水当量的模拟也显著偏低,但模式对乌拉尔山以西的东欧平原、我国北方及蒙古地区冬季雪水当量的模拟却比卫星遥感资料显著偏大,此外模式对堪察加半岛及以北的西伯利亚东北部地区的雪水当量也明显偏大。对于青藏高原地区,虽然部分模式可以模拟出青藏高原东部的雪水当量大值区,但大多数模式对青藏高原西部雪水当量的模拟却明显偏大,存在虚假的大值中心。对遥感反演资料的EOF(Empirical Orthogonal Function)分解表明,对于EOF第一个模态所对应欧亚大陆全区一致的年代际变化特征,仅有少数模式具有一定的模拟能力,大多数模式以及多模式集合的结果均未能予以反映;对应于欧亚大陆雪水当量年际变化的EOF第二模态而言,仅有少数模式(如俄罗斯的INMCM4)具有一定的再现能力,绝大多数模式对该模态及其时间演变的特征没有模拟能力。比较CMIP5多模式的集合预估结果与1981~2005年基准时段的雪水当量,可以发现在RCP4.5排放情景下,西伯利亚中东部地区的雪水当量相对于基准时段显著增加,区域平均的增加量在21世纪前、中、后期分别为4.1mm、5.4 mm和6.8 mm,且随时间增加得更显著;对90°E以西的欧洲大陆和青藏高原地区,其雪水当量则相对减少,减少的幅度和显著性也随时间而增大。就雪水当量的相对变化而言,在欧亚大陆东北部存在雪水当量相对变化的大值区,在21世纪后期相对变化显著区大都在5%~10%;但在青藏高原、斯堪的纳维亚半岛进和东欧平原,并没有发现雪水当量相对变化的髙值区,这是由于这些区域冬季雪水当量的幅值较大的缘故。RCP8.5情景下欧亚大陆雪水当量的变化特征与RCP4.5相类似,只是变化的幅度更大。

关键词： CMIP5模式雪水当量模式评估气候预估