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The difference analysis of physical-mechanical properties of sediments in the central South Yellow Sea and Zhe-Min coastal area in China

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Acta Oceanologica Sinica 2017年第7期36卷 77-85页

作者： XU Yuanqin LI Ping LI Peiying du Jun LIU Lejun GAO Wei LIU Jie Key Laboratory of Marine Sedimentology and Environmental Geology The First Institute of OceanographyState Oceanic AdministrationQingdao 266061China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China Research Center for Islands and Coastal Zones The First Institute of OceanographyState Oceanic AdministrationQingdao 266061China Marine Engineering Environment and Geomatic Center The First Institute of OceanographyState Oceanic AdministrationQingdao 266061China

The difference analysis of physical-mechanical properties of muddy sediments is made in the central South Yellow Sea and the Zhe-Min（Zhejiang Province to Fujian Province of China） coastal area. The results show that sediments in the two regions are both dominated by mud. There are perfect negative power function correlations between the water content and the density, the compression coefficient and the compression modulus; a good positive power function correlation between the liquid limit and the plastic limit, a perfect positive linear correlation between the water content and the void ratio, and a perfect polynomial function correlation between the miniature vane shear strength and the pocket penetration resistance. In general, compared with sediments in the Zhe-Min coastal area, sediments in the central South Yellow Sea possess high water content, high void ratio,low density, high plasticity, high compressibility, low shear strength. The causes of the differences between physical-mechanical properties of sediments are analyzed from the topographic features, material sources,hydrodynamic conditions, deposition rate, and material composition. Compared with the Zhe-Min coastal area,the central South Yellow Sea is far from the Mainland and low-lying; has poor hydrodynamic condition; the materials diffused to the area are less and dominated by fine clay, have the high content of smectite and organic matters. These factors lead to sediments of the central South Yellow Sea has the higher water content, the higher plasticity, the lower density, and the lower strength than sediments in the Zhe-Min coastal area.

关键词： sediment Zhe-Min coastal area central South Yellow Sea physical-mechanical properties difference analysis

Microparticle Effect of Carbon Dioxide Hydrate Crystal Nucleus in Reaction Kettle

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Journal of Renewable Materials 2021年第4期9卷 651-669页

作者： Yujie Bai Youquan Huang Guangsheng Cao Xiaohan Nan Qingchao Cheng Lei Wang Tong du MOE Key Laboratory for Enhanced Oil and Gas Recovery Northeast Petroleum UniversityDaqingChina Petro China Jidong Oilfield Company TangshanChina Oil Production Engineering Research Institute of Daqing Oilfield Petro ChinaDaqingChina School of Science Zhejiang UniversityHangzhou310000China

This study analyzed the partial effect of carbon dioxide hydrate in reaction kettle *** particle and bubble characteristics of the crystal nucleus during carbon dioxide hydrate decomposition were observed under the *** results showed that in the temperature range of 0.5℃–3.5℃,the pressure range of 3 MPa–5.5 MPa,phase characteristics in the reaction kettle changed in a complex fashion during carbon dioxide hydrate *** hydrate decomposition,numerous carbon dioxide bubbles were produced,mainly by precipitation at high temperatures or in the hydrate cage *** hydrate crystal nucleus initially exhibited fluidity in the ***,as the reaction progressed,the hydrate crystal nucleus migrated upward under the influence of gravity and carbon dioxide diffused into the aqueous ***,the hydrate was formed and accumulated,finally forming a solid carbon dioxide hydrate layer.

关键词： Carbon dioxide hydrate decomposition induction time particle characteristics

Prediction of sorghum miRNAs and their targets with computational methods

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Chinese Science Bulletin 2010年第13期55卷 1263-1270页

作者： du JiangFeng WU YongJun FANG XiaoFeng CAO JunXia ZHAO Liang TAO ShiHeng Bioinformatics Center Northwest Agricultural & Forestry University Yangling 712100 China College of Life Sciences Northwest Agricultural & Forestry University Yangling 712100 China

microRNAs 是 21-nt 的一个班在 post-transcriptional 起关键作用的长、非编码、最新识别的 RNA 基因规定。他们的目标涉及各种各样的生物过程，包括开发，新陈代谢，和压力反应。尽管很多 miRNAs 在许多种类被报导了，在蜀黍的 miRNAs... 详细信息

microRNAs 是 21-nt 的一个班在 post-transcriptional 起关键作用的长、非编码、最新识别的 RNA 基因规定。他们的目标涉及各种各样的生物过程，包括开发，新陈代谢，和压力反应。尽管很多 miRNAs 在许多种类被报导了，在蜀黍的 miRNAs 的报告是有限的。基于 genomic 调查顺序(GSS ) 和 microRNA (miRNA ) 使用相同搜索第二等的结构， 17 新 miRNAs 的一个总数在这个工作被识别。他们被发现在 11 个 miRNA 家庭之中不均匀的分布式。一些 miRNA 基因在多重地点并且在超过一 genomic 上下文被发现。大多数 miRNAs 在一样的王国以内被保存，但是我们在蜀黍发现 sbi-miR127 和 sbi-miR466 与 H 显示出保存。现代人并且 M。musculus 分别地。经由联机软件 miRU 的那些 17 新 miRNAs 的分析证明他们可能调整 64 目标基因，其大多数涉及 RNA 处理，新陈代谢，房间周期，蛋白质降级，压力反应和交通。11 个 miRNA 家庭中的至少 7 个指向在新陈代谢和压力反应是必要的蛋白质，包括 NADPH 细胞色素 P450 reductase， nucleoside diphosphate kinase 和 superoxide dismutase，建议 miRNAs 起在生物过程的一个必要作用。

关键词： miRNA 高粱细胞色素P450 超氧化物歧化酶计算预测应激反应新陈代谢

A new method of combined rock drilling

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International Journal of Mining Science and Technology 2014年第1期24卷 1-6页

作者： Tang Jiren Lu Yiyu Ge Zhaolong Xia Binwei Sun Huijuan du Peng State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing University National & Local Joint Engineering Laboratory of Gas Drainage in Complex Coal Seam Chongqing University Mechanical Engineering College Chongqing Industry Polytechnic College

Based on the technologies of traditionally mechanical drilling and water jet,we propose a new method of abrasive water jet in combination with rock drilling,and establish a combined rock drilling system for the gas *** study chose the common sandstone and silicon limestone as the rock sample.A series of experiments were completed in the case of dry drilling,existing technology drilling,combined drilling with high pressure water jet and combined drilling with abrasive water jet,*** drilling efficiency and performance were contrasted and analyzed in *** results indicate that it is better to choose the method of combined drilling with the high-pressure water jet for soft *** method of combined drilling with abrasive water jet is feasible for the hard rock drilling and has higher drilling efficiency and *** this paper,compared with the existing technology,the drilling depth has increased by about 65%,the axial force and torque have reduced by about 14%and 17%,respectively,and the drill wear reduces obviously in the same conditions.

关键词： Gas extraction Drilling Abrasive water jet Mechanical bit

Pretreating near infrared spectra with fractional order Savitzky–Golay differentiation(FOSGD)

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Chinese Chemical Letters 2015年第3期26卷 293-296页

作者： Kai-Yi Zheng Xuan Zhang Pei-Jin Tong Yuan Yao Yi-Ping du Shanghai Key Laboratory of Functional Materials Chemistry and Research Centre of Analysis and TestEast China University of Science and Technology Department of Chemical Engineering National Tsing Hua University

With the aid of Riemann–Liouville fractional calculus theory,fractional order Savitzky–Golay differentiation（FOSGD） is calculated and applied to pretreat near infrared（NIR） spectra in order to improve the performance of multivariate *** to integral order Savitzky–Golay differentiation（IOSGD）,FOSGD is obtained by fitting a spectral curve in a moving window with a polynomial function to estimate its coefficients and then carrying out the weighted average of the spectral curve in the window with the *** NIR datasets including diesel,wheat and corn datasets were utilized to test this *** results showed that FOSGD,which is easy to compute,is a general method to obtain Savitzky–Golay smoothing,fractional order and integral order *** order differentiation computation to the NIR spectra often improves the performance of the PLS model with smaller RMSECV and RMSEP than integral order ones,especially for physical properties of interest,such as density,cetane number and hardness.

关键词： Golay FOSGD fractional fitting smoothing utilized compute polynomial Liouville calibration

Crude enzyme immobilization‑based cell‑free system for efficient N‑acetylneuraminic acid biosynthesis aided by N‑terminal coding sequence screening

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Systems Microbiology and Biomanufacturing 2023年第3期3卷 479-488页

作者： Peng Wen Xueqin Lv Long Liu Jianghua Li Guocheng du Yanfeng Liu Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of EducationSchool of BiotechnologyJiangnan UniversityWuxi 214122China Science Center for Future Foods Jiangnan UniversityWuxi 214122China Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology Jiangnan UniversityWuxi 214122China Jiangsu Province Engineering Research Center of Food Synthetic Biotechnology Jiangnan UniversityWuxi 214122China

N-acetylneuraminic acid(NeuAc)is an important nutrient that plays a key role in brain development in infants NeuAc is mainly produced by extraction from natural resources such as edible birds’s nests,crucian eggs,caviar and human breast *** extraction process is complicated,resulting in the disadvantages of low NeuAc content and low recovery *** this study,a crude enzyme immobilization-based cell-free system(CEICFS)was developed for efficient NeuAc ***,N-terminal coding sequences that improved the expression levels of N-acetylglucosamine-2-epimerase(AGE)and N-acetylneuraminic acid aldolase(NanA)were obtained by high-throughput *** these sequences resulted in up to 1.5-fold(1.2-fold)increase in AGE(NanA)enzyme *** then,a CEICFS for NeuAc biosynthesis was proposed by directly immobilizing crude enzyme containing AGE and NanA on amino ***,NeuAc production from GlcNAc using CEICFS in one reactor was carried out,resulting 68 g/L of NeuAc and the highest productivity of 6.8 g/L/***,the enzyme activity was still higher than 75%after five repeated *** functional properties of CEICFS were studied and compared to those of the free enzyme,immobilization can extend the application of enzyme to some harsh environments,such as low temperature and acidic ***,CEICFS with excellent heat resistance,storage stability and reusability exhibit great potential for industrial application.

关键词： N-acetylneuraminic acid Immobilization Cell-free system N-terminal coding sequences

Underlying topography and forest height estimation from SAR tomography based on a nonparametric spectrum estimation method with low sidelobes

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International Journal of Digital Earth 2022年第1期15卷 2184-2201页

作者： Youjun Wang Xing Peng Qinghua Xie Xinwu Li Xiaomin Luo Yanan du Bing Zhang School of Geography and Information Engineering China University of Geosciences (Wuhan)WuhanPeople’s Republic of China Aerospace Information Research Institute Chinese Academy of SciencesBeijingPeople’s Republic of China School of Geographical Sciences Guangzhou UniversityGuangzhouPeople’s Republic of China School of Geomatics Liaoning Technical UniversityFuxinPeople’s Republic of China

The underlying topography and forest height play an indispensable role in many fields,including geomorphology,civil engineering construction,forest investigation,and the modeling of natural *** a new microwave remote sensing technology with three-dimensional imaging capability,synthetic aperture radar(SAR)tomography(TomoSAR)has already been proven to be an important tool for underlying topography and forest height *** spectrum estimation methods have now been proposed for ***,most of the commonly used methods are susceptible to noise and inevitably produce sidelobes,resulting in a reduced accuracy for the inversion of forest structural *** this paper,to solve this problem,a nonparametric spectrum estimation method with low sidelobes-the G-Pisarenko method-is *** method performs a logarithmic operation on the covariance matrix to obtain the main scattering characteristics of the objects of interest while suppressing the noise as much as *** effectiveness of the proposed method is demonstrated by the use of both simulated data and P-band airborne SAR data from a tropical forest region in Gabon,*** results show that the proposed method can reduce the sidelobes and improve the estimation accuracy for the underlying topography and forest height.

关键词： Underlying topography forest height TomoSAR G-Pisarenko method sidelobes

The Correlation between the Power Quality Indicators and Entropy Production Characteristics of Wind Power+Energy Storage Systems

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Energy Engineering 2024年第10期121卷 2961-2979页

作者： Caifeng Wen Boxin Zhang Yuanjun Dai Wenxin Wang Wanbing Xie Qian du School of Energy and Power Engineering Inner Mongolia University of TechnologyHohhot010080China Ministry of Education Key Laboratory ofWind and Solar Energy Utilization Technology Hohhot010080China School of Mechanical Engineering Shanghai Institute of Electrical EngineeringShanghai201306China School of Civil Engineering Inner Mongolia University of TechnologyHohhot010051China

Power quality improvements help guide and solve the problems of inefficient energy production and unstable power output in wind power *** purpose of this paper is mainly to explore the influence of different energy storage batteries on various power quality indicators by adding different energy storage devices to the simulated wind power system,and to explore the correlation between systementropy generation and various indicators,so as to provide a theoretical basis for directly improving power quality by reducing loss.A steady-state experiment was performed by replacing the wind wheel with an electric motor,and the output power qualities of the wind power systemwith andwithout energy storagewere compared and ***,the improvement effect of different energy storage devices on various indicatorswas ***,based on the entropy theory,the loss of the internal components of the wind power system generator is simulated and explored by Ansys *** the analysis of power quality evaluation indicators,such as current harmonic distortion rate,frequency deviation rate,and voltage fluctuation,the correlation between entropy production and each evaluation indicator was explored to investigate effective methods to improve power quality by reducing entropy *** results showed that the current harmonic distortion rate,voltage fluctuation,voltage deviation,and system entropy production are positively correlated in the tests and that the power factor is negatively correlated with system entropy *** the frequency range,the frequency deviationwas not significantly correlated with the systementropy production.

关键词： Wind power system entropy production system losses power quality indexes battery energy storage

The Integration of dual-Domain Method for Estimating the Volatility of Financial Assets

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Journal of Mathematical Research and Exposition 2010年第3期30卷 507-518页

作者： Xue Qiao du Xu Guo YE Department of Mathematics Hefei University of Technology Anhui 230009 P. R. China

Time- and state-domain methods are two common approaches for nonparametrically estimating the volatility of financial assets. Economic conditions vary over time in real financial market. It is reasonable to expect that volatility depends on both time and price level for a given state variable. Recently, Fan, et al （2007） proposed the idea of dynamically integrated method in both time-and state domain. This idea has become an interesting topic in the estimation of volatility. In this paper, our purpose is to discuss the integrated method in the estimation of volatility. Simulations are conducted to demonstrate that the newly integrated method outperforms some old ones, and the results of simulations demonstrate this fact. Furthermore, we establish its asymptotic properties.

关键词： Volatility estimation integrated estimator.