RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 원문제공처
        • 등재정보
          펼치기
        • 학술지명
          펼치기
        • 주제분류
        • 발행연도
          펼치기
        • 작성언어
        • 저자
          펼치기

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • Chemical Composition and Cold Flow Property of Cottonseed Oil Biodiesel Fuel

        Yongbin Lai,Junfeng Shu,Xiu Chen,Yinnan Yuan,Lei Zhong,Yuqi Zhang,Menghong Yuan,Bo Wang,Pen Wang 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.2

        The Cottonseed oil methyl ester (COME) was prepared using an alkali - catalyzed trans esterification reaction, and its chemical composition and cold flow properties (CFP) were studied. Two approaches, viz. blending with petrodiesel and treating with cold flow improver (CFI) were used to improve the CFP of COME. The results showed that COME was mainly composed of fatty acid methyl esters (FAMEs): C14:0–C22:0, C16:1–C20:1, C18:2 and C18:3–C20:3. The mass fractions of saturated and unsaturated FAMEs were 27.69% and 71.65%, respectively. The cold filter plugging point (CFPP) and kinematic viscosity (KV) at 40 °C of COME are -1 °C and 4.63 mm2/s respectively. Blending with -10 petrodiesel (-10PD) and 0 petrodiesel (0PD) can decrease the CFPP of COME/-10PD (B30-B40) and COME/0PD (B40-B50) -12 and -8 °C respectively. With the increase in petrodiesel content, the KV at 40 °C of blending oil decreased, and viscosity-temperature characteristics of blending oil were improved. When used Flow Fit (≤3vol.%), the CFPPs were reduce from COME/- 10PD B5, B7, B10, B20, B50 and COME -8, -8, -9, -11, -11 and -1 °C to -28, -27, -26, -25, -16 and -5 °C respectively; COME/0PD -3, -3, -4, -5, -8 and -1 °C to - 26, -25, -24, -24, -16 and -5 °C respectively.

      • A Novel Synchronization Technique for High Frequency Rectifier in Wireless Power Transfer

        Yongbin Jiang,Min Wu,Zexian Zeng,Yonghui Liu,Xiufang Hu,Laili Wang,Yue Wang 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

        This paper presents a novel synchronization technique for high frequency rectifier in wireless power transfer (WPT). To overcome the drawbacks of traditional phase-locked method based on DSP controller in high frequency rectifier, a novel phase-locked loop combined with the chained trigger mode (PLL-CTM) is proposed. The reasons why the driver pulses lose have been disclosed in detail. Then, the problem of pulse losing can be solved based on PLL-CTM. Finally, a 500W WPT prototype is built to verify the validity of the proposed synchronization technique.

      • KCI등재

        Catalytic reduction of CO2 to HCO2 by nanoscale nickel-based bimetallic alloy under atmospheric pressure

        Yi Zhao,Tianhao Wang,Yongbin Wang,Runlong Hao,Han Wang,Yuhong Han 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.77 No.-

        Carbon dioxide (CO2) was converted into formate (HCO2) in a catalytic reduction system mainlycomposed of potassium borohydride (KBH4) and nanoscale bimetallic nickel–copper alloy (NBN–C), inwhich, the average CO2 conversion efficiency of 41.92% was obtained under the optimal experimentalconditions, with a HCO2selectivity of 53.42%. Various characterization methods were employed toinvestigate the physicochemical properties of NBN–C and the results indicated that NBN–C was a coreshellmesoporous catalyst with key active sites containing Ni0 and Cu0, at which the catalytic reduction ofCO2 took place. The reaction mechanism was proposed based on these characterizations and relevantliteratures.

      • SCISCIESCOPUS

        Structural insight into the carboxylesterase BioH from <i>Klebsiella pneumoniae</i>

        Wang, Lulu,Chen, Yuanyuan,Shang, Fei,Liu, Wei,Lan, Jing,Gao, Peng,Ha, Nam-Chul,Nam, Ki Hyun,Dong, Yuesheng,Quan, Chunshan,Xu, Yongbin Elsevier 2019 Biochemical and biophysical research communication Vol.520 No.3

        <P><B>Abstract</B></P> <P>The BioH carboxylesterase which is a typical α/β-hydrolase enzyme involved in biotin synthetic pathway in most bacteria. BioH acts as a gatekeeper and blocks the further elongation of its substrate. In the pathogen <I>Klebsiella pneumoniae</I>, BioH plays a critical role in the biosynthesis of biotin. To better understand the molecular function of BioH, we determined the crystal structure of BioH from <I>K. pneumoniae</I> at 2.26 Å resolution using X-ray crystallography. The structure of KpBioH consists of an α-β-α sandwich domain and a cap domain. B-factor analysis revealed that the α-β-α sandwich domain is a rigid structure, while the loops in the cap domain shows the structural flexibility. The active site of KpBioH contains the catalytic triad (Ser82-Asp207-His235) on the interface of the α-β-α sandwich domain, which is surrounded by the cap domain. Size exclusion chromatography shows that KpBioH prefers the monomeric state in solution, whereas two-fold symmetric dimeric formation of KpBioH was observed in the asymmetric unit, the conserved Cys31-based disulfide bonds can maintain the irreversible dimeric formation of KpBioH. Our study provides important structural insight for understanding the molecular mechanisms of KpBioH and its homologous proteins.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Crystal structure of <I>K. pneumoniae</I>BioH consists of an α-β-αsandwish domain and acapsubdomain. </LI> <LI> The active site of KpBioH contains the catalytic triad (Ser82-Asp207-His235). </LI> <LI> The Arg138, Arg142, Arg155, and Arg159 of KpBioH may play an important role in the binding of the substrates like ACP. </LI> <LI> The Cys31-based disulfide bonds can maintain the irreversible dimeric formation of KpBioH. </LI> </UL> </P>

      • Study on Volatility of Palm Oil Biodiesel/-10 Petrodiesel by Thermogravimetric Analysis Technique

        Yongbin Lai,Peng Wang,Xiu Chen,Yinnan Yuan,Junfen Rong,Guang Wu,Yijun Zhou,Lei Zhong,Yuqi Zhang 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.2

        Palm methyl ester (PME) was prepared from palm oil through transesterification using NaOH as catalyst. Chemical composition of the PME and -10 petrodiesel (-10PD) was determined by gas chromatography-mass spectrometer (GC-MS). The PME and -10PD were characterized for their fuel properties including density, kinematic viscosity, and flash point, cold filter plugging point, sulfur content, copper strip corrosion and oxidative stability. Volatility was measured by thermogravimetric analysis (TGA). Volatile index was proposed to describe PME/-10PD volatility. A good correlation model was put forward for calculating the PME/-10PD volatility by PME blending ratio. The study showed that PME was mainly composed of long chain fatty acid methyl esters (FAMEs): C14:0-C24:0, C16:1-C22:1, C18:2 and C18:3. -10PD was mainly composed of long chain alkanes: C8-C26. The fuel properties of PME were within the limits prescribed in the GB/T 20828-2007 standards for biodiesel. With respect to -10PD, volatilization of PME was stronger and quicker, but volatilization onset at higher temperature. The volatilization onset temperatures of PME and -10PD were 448.9 and 361.7 K respectively; and the volatile indexes were 1.76E-04 and 3.64E-05 respectively. The PME/-10PD volatility had relation to PME blending ratio. The volatility of B0-B20 was very close to the -10PD. The volatility of B20-B100 was better with increasing the PME blending ratio.

      • KCI등재후보

        Cytosolic 5′-Methylthioadenosine/ S-Adenosylhomocysteine Nucleosidase MtaN from Mycobacterium. smegmatis: purification, crystallization and X-ray crystallographic analysis

        Lulu Wang,Yuanyuan Chen,Wei Liu,Jing Lan,Fei Shang,Nam-Chul Ha,Yuesheng Dong,Chunshan Quan,Yongbin Xu 한국구조생물학회 2019 Biodesign Vol.7 No.3

        Mycobacterium tuberculosis is a dangerous pathogen, and it can cause the most deadly disease tuberculosis (TB). Nonpathogenic Mycobacterium smegmatis is an important model for studying the M. tuberculosis. M. smegmatis 5’-Methylthioadenosine/S-adenosyl-L-homocysteine nucleosidases (MtaNs) catalyze the hydrolysis of adenine from 5’-methylthioadenosine (MTA), MtaNs cleave the glycosidic bond of MTA or S-adenosylhomocysteine (SAH) irreversibly. In this study, MtaN from M. smegmatis (MsMtaN) was successfully expressed and purified using Ni-NTA affinity, Q anionexchange and gel-filtration chromatography. The protein crystal was obtained and diffracted to a resolution of 2.0 Å. The crystal belonged to the orthorhombic space group P1211, with unit-cell parameters of a =57.6, b = 172.6, and c = 183.3 Å. The Matthews coefficient and solvent content were estimated to be 2.32 Å3 Da-1 and 47%, respectively, assuming that the asymmetric unit contained only one recombinant protein molecule. Size-exclusion chromatography suggested that MsMtaN prefer to exist as tetramer in solution.

      • KCI등재

        Distribution of Phytic Acid and Associated Catabolic Enzymes in Soybean Sprouts and Indoleacetic Acid Promotion of Zn, Fe, and Ca Bioavailability

        Xinkun Wang,Runqiang Yang,Xiaolin Jin,Yulin Zhou,Yongbin Han,Zhenxin Gu 한국식품과학회 2015 Food Science and Biotechnology Vol.24 No.6

        Phytic acid is involved in storage of phosphorus and minerals in soybeans. The effects of 6 basic plant hormones on phytic acid degradation were investigated. After 6 days of germination, phytic acid contents in soybean sprouts decreased by 70%, compared with day 0 soybeans. Zn and Fe bioavailability of 6-day-old germinating soybean both significantly increased (p<0.05), by contrast, Ca bioavailability decreased compared with controls. Phytic acid was detectable only in cotyledons of soybean sprouts during germination. In germinating soybeans, 39.19-45.85% and 54.15-60.81% of phytase existed in embryos and cotyledons, respectively. Unlike phytase, acid phosphatase was present mainly in cotyledons (92.57-97.51%). Among the 6 hormones, 50 mg/L indoleacetic acid (IAA) brought the highest degradation value to phytic acid content, meanwhile, Zn, Fe, and Ca bioavailability of IAA-treated soybeans were significantly (p<0.05) improved, compared with that of the control, respectively.

      • Hexameric assembly of membrane fusion protein YknX of the sporulation delaying efflux pump from <i>Bacillus amyloliquefaciens</i>

        Xu, Yongbin,Jo, Inseong,Wang, Lulu,Chen, Jinli,Fan, Shengdi,Dong, Yuesheng,Quan, Chunshan,Ha, Nam-Chul Elsevier 2017 Biochemical and biophysical research communication Vol.493 No.1

        <P><B>Abstract</B></P> <P>Membrane fusion proteins (MFPs) play an essential role in the action of the drug efflux pumps and protein secretion systems in bacteria. The sporulation delaying protein (SDP) efflux pump YknWXYZ has been identified in diverse <I>Bacillus</I> species. The MFP YknX requires the ATP-binding cassette (ABC) transporter YknYZ and the Yip1 family protein YknW to form a functional complex. To date, the crystal structure, molecular function and mechanism of action of YknX remain unknown. In this study, to characterize the structural and biochemical roles of YknX in the functional assembly of YknWXYZ from <I>B. amyloliquefaciens</I>, we successfully obtained crystals of the YknX protein that diffracted X-rays to a resolution of 4.4 Å. We calculated an experimentally phased map using single-wavelength anomalous diffraction (SAD), revealing that YknX forms a hexameric assembly similar to that of MacA from Gram-negative bacteria. The hexameric assembly of YknX exhibited a funnel-like structure with a central channel and a conical mouth. Functional studies <I>in vitro</I> suggest that YknX can bind directly to peptidoglycan. Our study provides an improved understanding of the assembly of the YknWXYZ efflux pump and the role of YknX in the complex.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The functional and structural properties of the YknX from <I>B. amyloliquefaciens.</I> </LI> <LI> The three-dimensional structure of MFP YknX and it has a strong affinity toward peptidoglycan. </LI> <LI> The YknX may forms a hexameric assembly in the crystal packing. </LI> <LI> The YknX displayed a similar upside-down, funnel-shaped orientation as <I>Aa</I> MacA. </LI> </UL> </P>

      • KCI등재

        The Fabrication of High-Aspect-Ratio Cylindrical Nano Tool using ECM

        Yufeng Wang,Ningsong Qu,Yongbin Zeng,Xiujuan Wu,Di Zhu 한국정밀공학회 2013 International Journal of Precision Engineering and Vol. No.

        With the miniaturization of various types of components and devices, micro- and nanometer-scale tools are increasingly in demand. Electrochemical machining (ECM) is a well-established technique for the fabrication of micro tools and nano tips. This paper presents a machining method for the fabrication of a high-aspect-ratio cylindrical nano tool using liquid membrane ECM, in which a straight reciprocating motion is applied to the anodic electrode. The method is based on periodic machining of the anodic rod within the amplitude of the straight reciprocating motion. In this process, the machining rate within amplitude varies periodically, allowing nano tools with high aspect ratios to be obtained by the presented method. Experiments were conducted to verify the proposed method. The influences of applied voltage, electrolyte concentration, amplitude and velocity of the straight reciprocating motion on the fabrication of cylindrical nano-electrode were investigated. By using this method, nano-electrodes with average diameters of several hundred nanometers and aspect ratios up to 70 were successfully fabricated.

      • Structural and Functional Analyses of Periplasmic 5′-Methylthioadenosine/<i>S</i>-Adenosylhomocysteine Nucleosidase from <i>Aeromonas hydrophila</i>

        Xu, Yongbin,Wang, Lulu,Chen, Jinli,Zhao, Jing,Fan, Shengdi,Dong, Yuesheng,Ha, Nam-Chul,Quan, Chunshan American Chemical Society 2017 Biochemistry Vol.56 No.40

        <P>The Gram-negative, rod-shaped bacterium Aeromonas hydrophila has two multifunctional 5/-methylthioadenosine/S-adenosylhomocysteine nucleosidase (MTAN) enzymes, MtaN-1 and MtaN-2, that differ from those in other bacteria. These proteins are essential for several metabolic pathways, including biological methylation, polyamine biosynthesis, methionine recycling, and bacterial quorum sensing. To gain insight into how these two proteins function, we determined four high-resolution crystal structures of MtaN-1 in its apo form and in complex with the substrates S-adenosyl-L-homocysteine, S'-methylthioadenosine, and 5'-deoxyadenosine. We found that the domain structures were generally similar, although slight differences were evident. The crystal structure demonstrates that AhMtaN-1 has an extension of the binding pocket and revealed that a tryptophan in the active site (Trp199) may playa major role in substrate binding, unlike in other MTAN proteins. Mutation of the Trp199 residue completely abolished the enzyme activity. Trp199 was identified as an active site residue that is essential for catalysis. Furthermore, biochemical characterization of AhMtaN-1 and AhMtaN-2 demonstrated that AhMtaN-1 exhibits inherent trypsin resistance that is higher than that of AhMtaN-2. Additionally, the thermally unfolded AhMtaN-2 protein is capable of refolding into active forms, whereas the thermally unfolded AhMtaN-1 protein does not have this ability. Examining the different biochemical characteristics related to the functional roles of AhMtaN-1 and AhMtaN-2 would be interesting. Indeed, the biochemical characterization of these structural features would provide a structural basis for the design of new antibiotics against A. hydrophila.</P>

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼