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The Co-Movements Between Crude Oil Price and Internet Concerns:Causality Analysis in the Frequency Domain

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Journal of Systems Science and Information 2020年第3期11卷 224-239页

作者： Jingjing LI ling tang ling LI School of Economics and Management Beihang UniversityBeijing 100191China International School of Economics and Management Capital University of Economics and BusinessBeijing 100070China

With the boom of web technology,Internet concerns(IC)have become emerging drivers of crude oil *** paper makes the first attempt to measure the frequency-varying co-movements between crude oil price and IC in five domains(i.e.,fundamentals,supply-demand,crisis,war and weather)by using the frequency causality test *** on the monthly Brent spot price and search volumes(SVs)captured by Google Trends from January 2004 to September 2019,new and complementary insights regarding the co-movements between crude oil price and IC are obtained.1)The co-movements between crude oil price and the IC of supply-demand,war,and weather support a neutral hypothesis at all frequencies due to the characteristics(low value or volatility)of these IC data.2)There is a unidirectional causal relationship between crude oil price and the IC of fundamentals,running from the latter to the former at low frequencies(long-term).3)There is a feedback relationship between crude oil price and the IC of crisis,with the IC of crisis driving crude oil price at medium and low frequencies(mid-and long-term)and crude oil price causing the IC of crisis to change *** conclusions of this paper provide important implications for both oil market economists and investors.

关键词： weather crude driving

Clinical outcomes of transperitoneal laparoscopic unroofing and fenestration under seminal vesiculoscopy for seminal vesicle cysts

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Asian Journal of Andrology 2018年第6期20卷 621-625页

作者： Rui zhi Xue Zheng-Yan tang zhi Chen Liang Huang Department of Urology Xiangya Hospital of Central South University Changsha 410000 China Provincial Laboratory for Diagnosis and Treatment of Genitourinary System Disease Changsha 410000 China

Symptomatic seminal vesicle cysts （SVCs）, especially those of a large size, can be removed by surgical treatments. Currently, open surgeries for SVC are rarely performed due to their extensive surgical trauma, and minimally invasive surgical therapies for treating seminal vesicle cysts are still in the early stages. In addition, relevant studies are mostly confined to case reports. In this study, we retrospectively reviewed 53 patients who had received transperitoneal laparoscopic unroofing or fenestration under seminal vesiculoscopy for SVC in our institution. Both surgeries decreased the cyst volume to a significant extent; however, according to the remnant lesion size after rechecking images, seminal vesiculoscopic fenestration tended to have a higher recurrence than laparoscopic unroofing. Regarding complications, two individuals in the laparoscopic unroofing group experienced ureteral injury and rectal injury, while patients in the fenestration group only had temporary hemospermia, which indicates that fenestration surgery tends to have less severe complications than laparoscopic unroofing. There was no solid evidence confirming semen improvement after these surgical therapies in our study. Future studies with a prospective design, larger sample size, and longer follow-up period are required to verify and further explore our findings.

关键词： cyst fenestration laparoscopy seminal vesicle unroofing vesiculoscopy

17-Dehydroxyholothurin A, a New Sulfated Triterpene Glycoside from Sea Cucumber Holothuna impatiens

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Chinese Chemical Letters 2006年第11期17卷 1454-1456页

作者： Peng SUN Yang Hua YI ling LI Min GUI Hai Feng tang Da zhi ZHANG Shi Long ZHANG Research Center for Marine Drugs Pharmacy School Second Military Medical University Shanghai 200433 Division of Antitumor Pharmacology State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 201203 Department of Pharmacy Xijing Hospital 4th Military Medical University Xi＇an 710032 Departrnent of Organic Chemistry Pharmacy School Second Military Medical University Shanghai 200433

Abstract： A new sulfated triterpene glycoside named as 17-dehydroxyholothurin A 1 was isolated from the sea cucumber Holothuria impatiens. Its structure was elucidated on the basis of spectroscopic data （2D NMR and MS） and chemical evidence. Compound 1 showed cytotoxic activity against cancer cell lines MKN-28, MFC-7, KB, HL-60 and Hep G2 with IC50 values of 1.98, 4.53, 2.01, 4.69 and 2.80 ×10^-6 tool/L, respectively.

关键词： Sea cucumber Holothuria impatiens 17-dehydroxyholothurin A triterpene glycoside.

Quartz luminescence dating of a centennial coastal foredune from Changle in Fujian Province,East China Sea

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Journal of Mountain Science 2022年第9期19卷 2601-2610页

作者： JIN Jian-hui LI zhi-zhong ling zhi-yong QIU Jun-jie Key Laboratory for Subtropical Resources and Environment of Fujian Province Fujian Normal UniversityFuzhou 350007China School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China Qinghai Institute of Salt Lakes Chinese Academy of SciencesXi'ning 810008China

The Aeolian foredunes in the southern coast of China are records of paleoenvironmental changes for marine monsoon region. Intensive studies have been conducted to decipher their formation and paleoenvironmental implications in which chronology played a key role. However, robust dating results are still limited due to the scarcity of organic materials for radiocarbon and the limited application of quartz optically stimulated luminescence(OSL). Here, we collected 11 OSL samples and 140 grainsize samples from the Changle section with a thickness of 7 m from a coastal foredune in Fujian Province. The dating results indicated that the section spanned a time period from 0.32±0.04 ka(depth of 700 cm) to 0.18±0.02 ka(depth of 80 cm), after removal of age outliers. According to the OSL ages and sedimentary structural characteristics, the section could be divided into two stages, i.e. the stable accumulation period with an age range of 0.32-0.18 ka from the depth of 700 cm to 80 cm, and the activation period above the depth of 60 cm, at which the dune erosion was retained. The foredune development due to increased transport of dune sediment at the top part of the section was the result of recent human *** the foredunes, normal cross-bedding was generated by seasonal changes in wind *** changes in the wind direction were the primary cause for various sedimentary bedding within the dunes.

关键词： Optically stimulated luminescence Grain size Oblique foredune Coastal South China

Polyethylenimine (PEI)g-comb-poly(ethylene glycol)-transferrin(I): Tumor-targeted Vector for Gene Delivery In-vitro

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Chinese Chemical Letters 2006年第1期17卷 113-116页

作者： Gu Ping tang zhi Yu WANG College of Life-Science. ZheJiang University Hangzhou 310028 Institute of Materials Research ＆ Engineering Singapore 3 Research Link 117602 The Second Hospital of Zhejiang University Hangzhou 310006

The work described the synthesis and evaluation of PEI-g-comb-PEG-transferrin as a potential system for gene therapy in vitro. The MW of PEG was 10KDa, and PEI was 2KDa. Its structure was identified by NMR, FT-IR and TGA spectroscopy. MTT assay found that at concentration up to 4000 n mol/L of the polymer, cell viability was over 85%. The bio-character of polymer/DNA complex was characterized by agarose gel electrophoresis, ethidium bromide exclusion and zeta-potential assay. The polymer could retardate DNA at N/P ratio 3.0-3.5 （mol/mol）. The particle size of the polymer/DNA complex was less than 300 nm. Transfection efficiency of the complex was studied in COS7 and NT2 cell lines.

关键词： PEI-g-Comb-PEG transferrin gene therapy transfection efficiency.

Mutual interference of layer plane and natural fracture in the failure behavior of shale and the mechanism investigation

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Petroleum Science 2021年第2期18卷 618-640页

作者： Peng Zhao ling-zhi Xie zhi-Chao Fan Lei Deng Jun Liu State Key Laboratory of Hydraulic and Mountain River Engineering College of Architecture and EnvironmentSichuan UniversityChengdu610065China Institute of New Energy and Low-Carbon Technology Sichuan UniversityChengdu610065China

Shale contains a certain amount of natural fractures,which affects the mechanical properties of *** this paper,a bonded-particle model in particle flow code(PFC)is established to simulate the failure process of layered shale under Brazilian tests,under the complex relationship between layer plane and natural ***,a shale model without natural fractures is verified against the experimental ***,a natural fracture is embedded in the shale model,where the outcomes indicate that the layer plane angle(marked asα)and the angle(marked asβ)of embedded fracture prominently interfere the failure strength anisotropy and fracture ***,sensitivity evaluations suggest that variable tensile/cohesion strength has a changeable influence on failure mechanism of shale,even for sameαor/andβ.To serve this work,the stimulated fractures are categorized into two patterns based on whether they relate to natural fracture or ***,four damage modes and the number of microcracks during the loading process are recognized quantitatively to study the mechanism of shale failure *** the failure mechanism determines the outcome of hydraulic fracturing in shale,this work is supposed to provide a significant implication in theory for the engineering operation.

关键词： PFC-based model Damage modes Tensile/cohesion strength Brazilian tests Hydraulic fracturing

High-Strength and High-Plasticity TWIP Steel for Modern Vehicle

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Journal of Materials Science & Technology 2005年第4期21卷 451-454页

作者： Zhenli MI Di tang ling YAN Jin GUO National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing Beijing100083 China

In this paper new high-strength and high-plasticity twinning induced plasticity （TWlP） steel for modern automobile body was investigated. Some basic experimental results were given. The results indicate the TWlP steel has excellent properties. It exhibits high ultimate tensile strength （600,--1100 MPa） and extremely large elongation of 60% to 90%.In the future it would be capable of satisfying the requirements of new generation of vehicle.

关键词： TWIP steel Strength Plasticity

Mineralization characteristics of pellets prepared by ultrafine magnetite concentrate:influence on metallurgical property and improving method

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Journal of Iron and Steel Research International 2023年第3期30卷 446-455页

作者： Xiao-hui Fan zhi-an Zhou Shu Wang Min Gan zhi-yun Ji Xu-ling Chen zhi-yuan Tian School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Northern Engineering and Technology Corporation MCCDalian 116600LiaoningChina

The reducing property of pellets prepared by ultrafine magnetite concentrate(UMC)and improving method were *** results show that the reduction degree of UMC pellets is only about 56%compared with that of pellets prepared from ordinary iron ore concentrate with relatively coarse particle size,which is significantly lower than the general reduction degree of about 70%.When the composite binder composed of bentonite and organic binder was added,the reduction degree was significantly increased to 69.66%.The revealed mechanism shows that the reduced pellets with common bentonite have a concentric structure,the oxidation gap between the inner and outer layers is obvious,and the outer dense oxide layer hinders the oxidation and reduction of the inner *** adding the composite binder,the organic components significantly improved the internal porosity of the pellets and the aggregation degree of ultrafine iron ore concentrate particles in the granulation process,forming a porous *** non-uniform double-layer structure is eliminated,and the increased pores are conducive to the internal diffusion of CO,and finally the reduction degree of pellets is increased to the level equivalent to that of ordinary magnetite pellets.

关键词： Ultrafine magnetite concentrate Mineralization characteristics Reduction degree Improving method Function mechanism

Spectral Analysis and Atmospheric Models of Microflares

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Chinese Journal of Astronomy and Astrophysics 2006年第5期6卷 597-607页

作者： Cheng Fang Yu-Hua tang zhi Xu Department of Astronomy Nanjing University Nanjing 210093 National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming650011

By use of the high-resolution spectral data obtained with THEMIS on 2002 September 5, the spectra and characteristics of five well-observed microflares have been analyzed. Our results indicate that some of them are located near the longitudinal magnetic polarity inversion lines. All the microflares are accompanied by mass motions. The most obvious characteristic of the Hα microflare spectra is the emission at the center of both Hα and CaⅡ 8542A lines. For the first time both thermal and non-thermal semi-empirical atmospheric models for the conspicuous and faint microflares are computed. In computing the non-thermal models, we assume that the electron beam resulting from magnetic reconnection is produced in the chromosphere, because it requires lower energies for the injected particles. It is found there is obvious heating in the low chromosphere. The temperature enhancement is about 1000-2200 K in the thermal models. If the non-thermal effects are included, then the required temperature increase can be reduced by 100-150 K. These imply that the Hα microflares can probably be produced by magnetic reconnection in the solar lower atmosphere. The radiative and kinetic energies of the Hα microflares are estimated and the total energy is found to be 10^27 - 4× 10^28 erg.

关键词： Sun Microflares - Sun spectrum - Sun semi-empirical modelling