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      • KCI등재

        Molecular Cloning and Function Analysis of an Anthocyanidin Synthase Gene from Ginkgo biloba, and Its Expression in Abiotic Stress Responses

        Feng Xu,Hua Cheng,Rong Cai,Lin Ling Li,Jie Chang,Jun Zhu,Feng Xia Zhang,Liu Ji Chen,Yan Wang,Shu Han Cheng,Shui Yuan Cheng 한국분자세포생물학회 2008 Molecules and cells Vol.26 No.6

        Anthocyanidin synthase (ANS, leucoanthocyanidin oxygenase), a 2-oxoglutarate iron-dependent oxygenase, catalyzed the penultimate step in the biosynthesis of the anthocyanin class of flavonoids, from the colorless leucoanthocyanidins to the colored anthocyanidins. The full-length cDNA and genomic DNA sequences of ANS gene (designated as GbANS) were isolated from Ginkgo biloba for the first time. The full-length cDNA of GbANS contained a 1062-bp open reading frame (ORF) encoding a 354-amino-acid protein. The genomic DNA analysis showed that GbANS gene had three exons and two introns. The deduced GbANS protein showed high identities to other plant ANSs. The conserved amino acids (H-X-D) ligating ferrous iron and residues (R-X-S) participating in 2-oxoglutarate binding were found in GbANS at the similar positions like other ANSs. Southern blot analysis indicated that GbANS belonged to a multi-gene family. The expression analysis by real-time PCR showed that GbANS expressed in a tissue-specific manner in G. biloba. GbANS was also found to be up-regulated by all of the six tested abiotic stresses, UV-B, abscisic acid, sucrose, salicylic acid, cold and ethylene, consistent with the promoter region analysis of GbANS. The recombinant protein was successfully expressed in E. coli strain with pET-28a vector. The in vitro enzyme activity assay by HPLC indicated that recombinant GbANS protein could catalyze the formation the cyanidin from leucocyanidin and conversion of dihydroquercetin to quercetin, suggesting GbANS is a bifunctional enzyme within the anthocyanidin and flavonol biosynthetic pathway.

      • KCI등재

        One-pot synthesis of 5-hydroxymethylfurfural directly from cottonseed hull biomass using chromium (III) chloride in ionic liquid

        Shui Wang,Yixin Qu,Yizhen Du,Ping Zhang,Xiaowei Cheng 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.12

        We studied the direct synthesis of 5-hydroxymethylfurfural (5-HMF) from cottonseed hull biomass underacid condition in one-pot. The influence of HCl dosage, reaction temperature and time, CrCl3·6H2O amount, and cotton-seed hull loading on the yield of 5-HMF was investigated. As a result, a 5-HMF yield up to 51% was obtained using 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) catalyzed with chromium (III) chloride at 130 oC for 2 h. The [Bmim]Cl/CrCl3·6H2O/HCl system was found to have high activity and selectivity for the dehydration of cellulose into 5-hydroxy-methylfurfural. This work provides a low cost, environment-friendly and energy-efficient process to directly convertraw biomass into bio-fuels and chemicals.

      • KCI등재

        Catalytic conversion of cellulose into 5-hydroxymethylfurfural over chromium trichloride in ionic liquid

        Shui Wang,Jidong Wang,Yizhen Du,Wenqian Zhang,Xiaowei Cheng 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.10

        An efficient method for converting cellulose into 5-hydroxymethylfurfural (5-HMF) using an inexpen-sive ionic liquid tetrabutylammonium chloride (TBAC) and relatively low-toxicity catalyst of chromium (III) trichloride(CrCl3·6H2O) was developed. The effects of hydrochloric acid loading, catalyst dosage, reaction temperature and timeon the yield of 5-HMF were surveyed to achieve optimal reaction conditions. A 5-HMF yield of 43.7% was obtainedwithin 90 min at 140 oC using oil-bath heating. Glucose and starch were also investigated as feedstock to produce 5-HMF in TBAC/CrCl3·6H2O system, in which the 5-HMF yield was considerable. After 5-HMF was extracted, TBAC/CrCl3 ·6H2Ocould be used for several runs.

      • KCI등재

        Pepsin and Laryngeal and Hypopharyngeal Carcinomas

        Cheng-Yi Yin,Sha-Sha Zhang,Jiang-Tao Zhong,Shui-Hong Zhou 대한이비인후과학회 2021 Clinical and Experimental Otorhinolaryngology Vol.14 No.2

        Laryngeal and hypopharyngeal carcinomas are common malignant tumors of the head and neck, and the incidence of both is increasing. Laryngopharyngeal reflux refers to the retrograde flow of gastric contents into the larynx, oropharynx, and/or nasopharynx. It remains controversial whether laryngopharyngeal reflux is a risk factor for laryngeal and hypopharyngeal cancers. The refluxing substances mainly include hydrochloric acid, pepsin, and occasionally bile acids and bile salts, as well as bacteria that colonize the gastrointestinal tract. Loss of epithelium in the mucous membrane of the larynx and hypopharynx is thought to be caused by pepsin. Here, we review the relationships between laryngopharyngeal reflux and both laryngeal and hypopharyngeal carcinomas, as well as the significance of pepsin, methods of clinical detection, and the mechanism of carcinogenesis.

      • KCI등재

        Synthesis and electrochemical performance of Li1þxV3O8 as cathode material prepared by citric acid and tartaric acid assisted solegel processes

        Miao Shui,Weidong Zheng,Jie Shu,Qingchun Wang,Shan Gao,Dan Xu,Liangliang Cheng,Lin Feng,Yuanlong Ren 한국물리학회 2013 Current Applied Physics Vol.13 No.3

        Lithium-ion battery cathode material Li1þxV3O8 is synthesized by a citric acid/tartaric acid assisted sol egel method and sintered at 350 C, 450 C and 550 C for 3 h for the formation of Li1þxV3O8 phase. The synthesized samples were fully characterized by FTIR, TG/DTA, XRD, SEM, EIS and chargeedischarge tests. Li1þxV3O8 material synthesized by tartaric acid assisted route and sintered at 450 C for 3 h shows best electro-chemical performance. It shows a high initial capacity of 249 mAh g1 and still reserves a discharge capacity of 260 mAh g1 after 50 cycles. Moreover, in the case of tartaric assisted products, no capacity decadence is observed in 50 cycles. XRD together with TG/DTA measurements reveal that compared with citric acid assisted products, the adoption of tartaric acid as chelating agent effectively lowers the crystallization temperature of amorphous Li1þxV3O8. Therefore, precursors obtained by tartaric acid route calcinated at 450 C for 3 h exhibit lower crystallinity and smaller grain size, which contributes to the better electrochemical performance of the cathode electrodes. From EIS measurements, the bulk resistance is reduced, which favors the intercalation and de-intercalation of lithium ions while cycling.

      • KCI등재

        Genetic Diversity and Structure of Cordyceps sinensis Populations from Extensive Geographical Regions in China as Revealed by Inter-Simple Sequence Repeat Markers

        Hong-Hui Liang,Zhou Cheng,Xiao-Ling Yang,Shan Li,Zu-Quan Ding,Tong-Shui Zhou,Wen-Ju Zhang,Jia-Kuan Chen 한국미생물학회 2008 The journal of microbiology Vol.46 No.5

        Cordyceps sinensis is one of the most valuable medicinal caterpillar fungi native to China. However, its productivity is extremely limited and the species is becoming endangered. The genetic diversity of eighteen C. sinensis populations across its major distributing regions in China was evaluated by inter-simple sequence repeat (ISSR) markers. A total of 141 markers were produced in 180 individuals from the 18 populations, of which 99.3% were polymorphic. The low average of Shannon (0.104) and Nei index (0.07) of the 18 populations indicates that there are little genetic variations within populations. For all 18 populations, estimates of total gene diversity (HT), gene diversity within populations (HS), coefficient of genetic differentiation (GST), and gene flow (Nm) were 0.170, 0.071, 0.583, and 0.357, respectively. This pattern suggests that the genetic diversity of C. sinensis is low and most of the ISSR variations are found among populations with little gene exchange. The 18 populations are divided into five groups based on the genetic distance and the grouping pattern matches with the geographic distribution along the latitudinal gradient. The five groups show obvious difference in the GST and Nm values. Therefore, the genetic diversification of C. sinensis populations may be determined by geographic isolation and the combined effects of life history characters and the interaction with host insect species. The information illustrated by this study is useful for selecting in situ conservation sites of C. sinensis.

      • KCI등재

        A comparative study of three collocation point methods for odd order stochastic response surface method

        Dian-Qing Li,Shui-Hua Jiang,Yong-Gang Cheng,Chuang-Bing Zhou 국제구조공학회 2013 Structural Engineering and Mechanics, An Int'l Jou Vol.45 No.5

        This paper aims to compare three collocation point methods associated with the odd order stochastic response surface method (SRSM) in a systematical and quantitative way. The SRSM with the Hermite polynomial chaos is briefly introduced first. Then, three collocation point methods, namely the point method, the root method and the without origin method underlying the odd order SRSMs are highlighted. Three examples are presented to demonstrate the accuracy and efficiency of the three methods. The results indicate that the condition that the Hermite polynomial information matrix evaluated at the collocation points has a full rank should be satisfied to yield reliability results with a sufficient accuracy. The point method and the without origin method are much more efficient than the root method, especially for the reliability problems involving a large number of random variables or requiring complex finite element analysis. The without origin method can also produce sufficiently accurate reliability results in comparison with the point and root methods. Therefore, the origin often used as a collocation point is not absolutely necessary. The odd order SRSMs with the point method and the without origin method are recommended for the reliability analysis due to their computational accuracy and efficiency. The order of SRSM has a significant influence on the results associated with the three collocation point methods. For normal random variables, the SRSM with an order equaling or exceeding the order of a performance function can produce reliability results with a sufficient accuracy. The order of SRSM should significantly exceed the order of the performance function involving strongly non-normal random variables.

      • KCI등재

        Optimal Filtering for Linear Discrete-Time Systems with Single Delayed Measurement

        Hong-Guo Zhao,Huan-Shui Zhang,Cheng-Hui Zhang,Xin-Min Song 대한전기학회 2008 International Journal of Control, Automation, and Vol.6 No.3

        This paper aims to present a polynomial approach to the steady-state optimal filtering for delayed systems. The design of the steady-state filter involves solving one polynomial equation and one spectral factorization. The key problem in this paper is the derivation of spectral factorization for systems with delayed measurement, which is more difficult than the standard systems without delays. To get the spectral factorization, we apply the reorganized innovation approach. The calculation of spectral factorization comes down to two Riccati equations with the same dimension as the original systems.

      • KCI등재

        THEORETICAL AND EXPERIMENTAL STUDY ON FLOW CHARACTERISTICS OF A DIAPHRAGM PUMP FOR UREA-SCR SYSTEMS

        Shu Dong Yang,You Cheng Shi,Xi Wei Pan,Yin Shui Liu 한국자동차공학회 2019 International journal of automotive technology Vol.20 No.4

        Urea selective catalytic reduction (SCR) is the primary technology used to reduce the nitrogen oxides (NOx) of diesel engine exhaust. To meet the requirements of an SCR system, a novel type of miniature diaphragm pump was designed. Based on the theory of large deflection of annular plates, the equilibrium equations of a diaphragm with a rigid inclusion were established, and the equations were solved by the nondimensional method and the finite difference method. Theoretical and approximated flow model for this pump were proposed. A theoretical relationship between back pressure, rigid inclusion size and volumetric efficiencies were calculated. To verify the validity of theoretical model, a prototype pump was fabricated and tested. Experimental results demonstrated that the flow is proportional to the pump speed. The deviation between theoretical, approximated flow and experimental flow was less than 4 % and 9.4 %, respectively. The difference between theoretical and experimental volumetric efficiency was varied from 2.7 % to 6.1 % when back pressure changed from 0 to 0.9 MPa. The volumetric efficiency was growing with the increasing of the rigid inclusion size. The pressures in the working chamber showed almost the same overall trends between the theoretical results and experimental values. The experimental results show that the proposed theoretical model is effective.

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