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Quartz Cement in Middle Jurassic Reservoir Sandstones in North Sea. A Review. Part Ⅰ: Occurrence and Character

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沉积学报 1999年第2期 98-103页

作者： zhang shao nan 1 knut bjrlykke 2 1 (Chengdu Univesity of Technology Chengdu 610059) 2 ( University of Oslo 0316 Oslo 3 Norway)

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ＩＮＴＲＯＤＵＣＴＩＯＮＱｕａｒｔｚｃｅｍｅｎｔｈａｓｂｅｅｎｅｘｔｅｎｓｉｖｅｌｙｓｔｕｄｉｅｄｉｎｒｅｃｅｎｔｙｅａｒｓ（ｅ．ｇ．ＭｃＢｒｉｄｅ，１９８９，Ｌａｎｄａｎｄｏｔｈｅｒｓ，１９９０，ＢｒｌｙｋｋｅａｎｄＥｇｅｂｅｒｇ，１９９３）．Ｉｔ...

关键词： quartz cement homogenezation temperature sandstone Brent Group North Sea

Studies on the SFD Properties of NdxGd1-xCa4O（BO3）3 Solid-solution Crystal

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Chinese Journal of Lasers 2000年第3期9卷 91-95页

作者： zhang Shujun-1 CHENG Zhenxiang-1 LI Guangming-1 WANG Changqing-2 HOU Xueyuan-3 SUN Yuming-3 Y. T. Chow-2 shao Zongshu-1 CHEN Huanchu-1 ( -1 State Key Lab. of Crystal Materials, Shandong University, Ji'nan 250100, China -2 Optoelectronics R 山东大学晶体材料国家重点实验室山东济南香港城市大学香港山东大学山东济南

Nd xGd 1-xCa 4O(BO 3) 3 (NdGdCOB) i s a new self-frequency-doubling (SFD) solid-solution crystal. The second-harmonic generation (SHG) phase-matching (PM) curves were calculated by using refractive indices. The d eff of NdGdCOB crystal along different PM directions were calculated according to the sellmeier equation and d ijk data in which the (θ=66.8°, φ=132.6°) PM direction has the highest d eff. SFD experiments were carried out with Ti∶sapphire CW laser and pulsed dye-laser. A green laser output power up to 225 mW at 530 nm was achieved from a 7×3×3 mm-3 crystal sample pumped by 1560 mW CW Ti∶sapphire laser. The lasing threshold of SFD was lower than 1.8 mW along the PM direction (66.8°,132.6°). The optical-optical conversion efficiency was 14.4%. The conversion efficiency was 7.7% when 10×3×3 mm-3 sample was side-pumped by the pulsed dye-laser tuned to 595.4 nm with 17.5 mJ energy and the lasing threshold is 1.2 mJ.

关键词： self-frequency-doubling conversion efficiency NdGdCOB crystal

Genetic Structure and Diversity of Parental Cultivars Involved in China Mainland Sugarcane Breeding Programs as Inferred from DNA Microsatellites

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Journal of Integrative Agriculture 2012年第11期11卷 1794-1803页

作者： QI Yong-wen PAN Yong-bao LAO Fang-ye zhang Chui-ming FAN Li-na HE Hui-yi LIU Ruin WANG Qin-nan LIU shao-mou LIU Fu-ye LI Qi-wei DENG Hai-hua Guangdong Key Laboratory of Sugarcane Improvement and Biorefinery Guangzhou Sugarcane Industry Research Institute Guangzhou 510316 P.R.China USDA-ARS Mid-South Area Sugarcane Research Laboratory Houma 70360 USA

To understand genetic structure and diversity of parental cultivars involved in China Mainland sugarcane breeding programs, 92 elite parents and 4 wild relatives were genotyped with 18 microsatellite DNA markers. The genetic similarity （GS） values among the cultivars ranged from 0.346 to 0.960 with an average of 0.533. Among the introduced cultivars, India accessions had the closest genetic distance to China Mainland accessions （0.447）, while Australia accessions have the furthest distance （0.503）. A comparison of allelic diversity among geographical origins showed that there were 22 China Mainland specific alleles, of which 28% were derived from native S. spontaneaum germplasm in China. Model-based genetic structure, clustering, and principal components analyses consistently revealed there were five groups within the 96 accessions. Groups 1, 2, 4, and 5 consisted of all cultivars and group 3 only contained wild germplasm. Group 2 was characterized as the Introduction group with 46 cultivars predominantly introduced from Australia, Taiwan of China, India, and USA. Groups 1, 4, and 5 consisted of cultivars mostly originated from China Mainland, defined as the Complex group, Yacheng lines group, and F134/CP72-1210 group, respectively, upon their pedigree. By understanding the genetic relationships among the parental cultivars, breeders can gain a rational basis for expanding the gene pool and select the best parental accessions for crossing.

关键词： genetic diversity microsatellite DNA marker population structure sugarcane

D609 induces vascular endothelial cells and marrow stromal cells differentiation into neuron-like cells

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Acta Pharmacologica Sinica 2004年第4期25卷 44-48页

作者： nan WANG, Chun-qing DU, shao-shan WANG, Kun XIE, Shang-li zhang, Jun-ying MIAO2 Institute of Developmental Biology, School of Life Science, Shandong University, Ji-nan 250100, China Institute of Developmental Biology School of Life Science Shandong University Ji-nan 250100 China

AIM: To investigate the effect of tricyclodecane-9-yl-xanthogenate (D609) on cell differentiation in vascular endo- thelial cells (VECs) and marrow stromal cells (MSCs). METHODS: Morphological changes were observed under phase contrast microscope. Electron microscope and immunostaining were used for VECs identification. The expressions of neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP) were examined by immunohistochemistry. RESULTS: After 6 h of induction with D609, some VECs showed morphological changes characteristic of neurones. 9 h later, more VECs became neuron-like cells. About 30.8 % of VECs displayed positive NSE (P1), while the expression of GFAP was negative. When MSCs were exposed to D609, the cells displayed neuronal morphologies, such as pyramidal cell bodies and processes formed extensive networks at 3 h. 6 h later, almost all of the cells exhibited a typical neuronal appearance, and 85.6 % of MSCs displayed intensive positive NSE, but GFAP did not express. CONCLUSION: D609 induces VECs and MSCs differentiation into neuron-like cells.

关键词： tricyclodecane-9-yl-xanthogenate cell differentiation vascular endothelial cells marrow stromal cells neuron-like cells

Regularization of mathematical model for chip flow angle catastrophe

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Advances in Manufacturing 2021年第4期9卷 568-579页

作者： shao-nan zhang Dong-Dong Cheng Liang-Shan Xiong School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China

The chip flow angle(CFA)catastrophe in double-edged cutting results in a significant reduction in the cutting force,which can benefit the ***,established potential functions(i.e.,cutting power calculation functions)of mathematical models for the CFA catastrophe are presented in the form of transcendental functions with two control parameters and one state parameter,which are extremely complex.A method is proposed herein to realize the regularization of the potential functions and establish mathematical models in a standard form and with complete content for the CFA *** this method,the potential function of the CFA catastrophe is expanded into a k-order Taylor polynomial at each midpoint of N end-to-end equally partitioned intervals of the state parameter using the Taylor function provided in *** potential function after piecewise Taylor expansion is transformed into the same form as the potential function of the standard cusp catastrophe model by truncating the first five terms of the Taylor polynomial and eliminating the third-order term of the state parameter with elementary ***,the regularization of potential function is ***,the regularization of equilibrium surface and bifurcation set can be realized based on the conclusions of the catastrophe *** errors of the potential function,equilibrium surface,and bifurcation set are defined to evaluate the effectiveness of this regularization *** problem of calculating regularization errors is regarded as an optimization ***‘‘simulannealbnd’’function provided in MATLAB is used to solve the *** the proposed method,the regularization of a mathematical model for the CFA catastrophe established by the predecessor is completed;a mathematical model(i.e.,standard cusp catastrophe model)in a standard form and with complete content for the CFA catastrophe is established;and the corresponding regularization errors

关键词： Chip flow angle(CFA)catastrophe Mathematical model Regularization Potential function Catastrophe theory Cusp catastrophe model

The Local and Global Existence of Solutions for a Generalized Camassa-Holm Equation

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Acta Mathematica Sinica,English Series 2013年第4期29卷 757-776页

作者： shao Yong LAI nan LI Jian zhang Department of Mathematics Southwestern University of Finance and Economics Department of Mathematics Sichuan Normal University

A fully nonlinear generalization of the Camassa-Holm equation is investigated. Using the 3 pseudoparabolic regularization technique, its local well-posedness in Sobolev space Hs（R） with s 〉 is established via a limiting procedure. Provided that the initial momentum （1 - 02）u0 satisfies the sign condition,the existence and uniqueness of global solutionsfor the equation are shown to be true in the space C.

关键词： Existence of global solutions Camassa-Holm type equation Pseudoparabolic regulariza-tion method

Characterization of countercurrent liquid-upward and solid-downward fluidized system

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Particuology 2022年第11期70卷 95-105页

作者： Enming zhang Keying Ma Yuanyuan shao Jesse Zhu Tian nan School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Department of Chemical&Biochemical Engineering Western UniversityLondonOntario N6A 3K7Canada Institute of shaoxing Tianjin UniversityZhejiang 312300China

Acting as an operating mode of fluidization,the flow characteristics of a countercurrent liquid–solid fluidized bed(CCLSFB)were experimentally investigated using a Plexiglas column of 1.5 m in *** liquid-upward and solid-downward fluidization was achieved under a limited solid flowrate before flooding ***“flooding”phenomena and the flooding velocity were identified by measuring the variations in pressure drop in the axial direction of the *** different methods were used to quantify the flooding point that led to the instability of the *** solids holdup profiles were also obtained from the pressure drop data along the column and the influences of device structure and operating conditions on the solids holdup were also *** types of particles with different diameters and densities were *** agreement was found between the experimental results and the mathematic prediction derived from the Richardson–Zaki equation on the data of the solids holdup.

关键词： Countercurrent fluidization Flooding Pressure drop Solids holdup Richardson-Zaki equation

Chemical composition and phytotoxic activity of the volatile oil of invasive Xanthium italicum Moretti from Xinjiang,China

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Journal of Arid Land 2013年第3期5卷 324-330页

作者： Hua shao YuanMing zhang Peng nan XiaoLi HUANG Chi zhang Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering School of Life SciencesFudan University State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences

Aerial parts of Xanthium italicum in an air tight container greatly inhibited root elongation of radish, implying that this invasive plant could release biologically active volatile organic compounds （VOCs） into the environment to affect other plants＇ growth. This phenomenon was further studied by evaluating the phytotoxic effects of X. italicum essential oil against two dicot plants, amaranth （Amaranthus mangostanus L.） and lettuce （Lectuca sativa L.）, and two monocot plants, wheat （Triticum aestivum Linn） and ryegrass （Lolium multiforum）, and analyzing the chemical composition of the oil. Among the 4 test species, amaranth was the most sensitive plant, 0.5μl/mL essential oil application resulted in a 50% reduction on root elongation, and 2.5 μl/mL essential oil almost completely inhibited its seedling growth. Wheat was the least sensitive species, whose root growth was reduced to 36% of control by 5 μl/mL essential oil. The essential oil exerted moderate inhibitory effect on both lettuce and ryegrass. Compared to a commercial herbicide-Harness, X. italicum oil exhibited stronger phytotoxicity on amaranth, lettuce and wheat, but weaker activity on ryegrass. The chemical composition of the essential oil isolated by hydrodistillation from the aerial parts of X. italicum Moretti was analyzed by GC/MS. Thirty two compounds were identified, representing 94.89% of total oil, which was found to be rich in monoterpene hydrocarbons （60.71%）. The main constituents of the oil were limonene （51.61%）, germacrene B （6.98%）, 6-cadinol （5.94%）, β-pinene （5.23%）, α-caryophyllene （5.1%） and bornyl acetate （3.15%）. Bioassay revealed the dominant constituent-limonene, was unlikely the responsible phytotoxic compound due to its low biological activity; rather, there might be other oil constituent（s） that either act alone, or work together, and possibly assisted by synergistic effect, to display the phytotoxic activity. Our results suggested that X. italicum might produce allelopathic V

关键词： allelopathy phytotoxicity essential oil volatile organic compounds Xanthium italicum

High-concentration sevoflurane exposure in mid-gestation induces apoptosis of neural stem cells in rat offspring

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Neural Regeneration Research 2018年第9期13卷 1575-1584页

作者： Yuan Wang shao-Wei Yin nan zhang Ping Zhao Department of Anesthesiology Shengjing Hospital of China Medical University Department of Obstetrics Shengjing Hospital of China Medical University Department of Neuroendocrine Pharmacology School of PharmacyChina Medical University

Sevoflurane is the most commonly used volatile anesthetic during *** viability of neural stem cells directly affects the development of the ***,it is unknown whether the use of sevoflurane during the second trimester affects the survival of fetal neural stem ***,in this study,we investigated whether exposure to sevoflurane in mid-gestation induces apoptosis of neural stem cells and behavioral *** gestational day 14,pregnant rats were anesthetized with 2% or 3.5% sevoflurane for 2 *** offspring were weaned at 28 days and subjected to the Morris water maze *** brains were harvested to examine neural stem cell apoptosis by immunofluorescence and to measure Nestin and SOX-2 levels by western blot assay at 6,24 and 48 hours after anesthesia as well as on postnatal day（P） 0,14 and *** endothelial growth factor（VEGF） and phosphoinositide 3-kinase（PI3 K）/AKT pathway protein levels in fetal brain at 6 hours after anesthesia were assessed by western blot *** to high-concentration（3.5%） sevoflurane during mid-gestation increased escape latency and path length to the platform,and it reduced the average duration spent in the target quadrant and platform crossing *** 6,24 and 48 hours after anesthesia and at P0,P14 and P28,the percentage of Nestin/terminal deoxynucleotidyl transferase d UTP nick end labeling（TUNEL）-positive cells was increased,but Nestin and SOX-2 protein levels were decreased in the hippocampus of the *** 6 hours after anesthesia,VEGF,PI3 K and phospho-AKT（p-AKT） levels were decreased in the fetal *** changes were not observed in animals given low-concentration（2%） sevoflurane ***,our findings indicate that exposure to a high concentration of sevoflurane（3.5%） in mid-gestation decreases VEGF,PI3 K and p-AKT protein levels and induces neural stem cell apoptosis,thereby causing learning and memory dysfunction in the offspring.

关键词： nerve regeneration sevoflurane neural stem cells apoptosis vascular endothelial growth factor PI3K p-AKT anesthesia learning memory developmental neurobiology neural regeneration