期刊文献+
共找到6篇文章
< 1 >
每页显示 20 50 100
Isolation and Identification of Alkali-Resistant 1,3-Propanediol Producing Strain
1
作者 zhifang zhao Caifang Wen +3 位作者 Guang Rong Ruiqing Liu Jianguo Xu Qingping Hu 《Advances in Microbiology》 2016年第12期917-926,共11页
1,3-Propanediol is a promising renewable resource produced by microbial production. It is mainly used in many synthetic reactions, particularly applied to the polymer synthesis and cosmetics industry. We described her... 1,3-Propanediol is a promising renewable resource produced by microbial production. It is mainly used in many synthetic reactions, particularly applied to the polymer synthesis and cosmetics industry. We described here the isolation of strain ZH-1, which has the ability of high production with 1,3-propanediol, from Fenhe River in China. It was classified as a member of K. pneumoniae after the study of phenotypic, physio-logical, biochemical and phylogenetic (16S rDNA). The initial glycerol concentration, fermentation time and pH value of strain ZH-1 were determined to be 50 g·L<sup>-1</sup>, 36 h and 8.0. Under these conditions, the practical yield of 1,3-PD was 18.53 g·L<sup>-1</sup> and a molar yield (mol<sub>1,3-PD</sub> mol<sub>Glycerol</sub>-1</sup> of 1,3-propanediol to glycerol of 0.497. In addition, we found that for the strain ZH-1, the optimum grown pH was 9.0, so we can deter-mine that it is a new member of alkali-resistant strains. 展开更多
关键词 1 3-Propanediol K. pneumoniae Identification Alkali-Resistant
下载PDF
Identifying the leucogranites in the Ailaoshan-Red River shear zone:Constraints on the timing of the southeastward expansion of the Tibetan Plateau 被引量:2
2
作者 Xiaohu He Shucheng Tan +4 位作者 Jiaxi Zhou Zheng Liu zhifang zhao Siqi Yang Yahui Zhang 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第3期765-781,共17页
The uplift of the Tibetan Plateau significantly affected the global climate system.However,the timing of its uplift and the formation of its vast expanse are poorly understood.The occurrence of two types of leucograni... The uplift of the Tibetan Plateau significantly affected the global climate system.However,the timing of its uplift and the formation of its vast expanse are poorly understood.The occurrence of two types of leucogranites(the two-mica leucogranites and garnet-bearing leucogranites) identified in the Ailaoshan-Red River(ASRR) shear zone suggests an extension event in the southeastern Tibetan Plateau.The age of these leucogranites could be used to constrain the timing of uplift and southeastward expansion of the plateau.Petrography,geochronology and geochemistry investigations,including Sr-Nd isotope analysis,were conducted on the two-mica leucogranites and garnet-bearing leucogranites from the ASRR shear zone.LA-ICP-MS zircon U-Pb dating indicates that these rocks were emplaced at ~27 Ma,implying that the Tibetan Plateau had already achieved maximum uplift prior to the late Oligocene.It subsequently started to expand southeastward as a result of crustal flow.Compared to classic metapelite-derived leucogranites from Himalaya,the two-mica leucogranites show high K_2 O/Na_2 O(1.31-1.92),low Rb/Sr,CaO,lower ^(87)Sr/^(86)Sr ratios(0.7089-0.7164) and higher ε_(Nd)(t)(-8.83 to-3.10).This whole-rock geochemical characteristics likely indicates a mixing source origin,composed predominantly of amphibolite with subordinated metapelite,which is also evidenced by ^(87)Sr/^(86)Sr vs.ε_(Nd)(t) diagram.However,The garnetbearing leucogranites with high SiO_2 contents(72.25-74.12 wt.%) have high initial ^(87)Sr/^(86)Sr ratios(0.7332-0.7535) and low ε_(Nd)(t)(-16.36 to 18.98),indicating that they are derived from the source comprised of metapelite and results of fluexed muscovite melting under lower crustal level,which is also evidenced by the Rb-Sr-Ba systematics.These leucogranites formed from partial melting of the thickened lower crust,which resulted in the formation of granitic melt that weakened the crust.The weakened crust aided the left-lateral strikeslip movement of the ASRR shear zone,triggering the escape of the Indochina terrane in the southeastern Tibetan Plateau during the late Oligocene. 展开更多
关键词 LEUCOGRANITES CRUSTAL flow Southeastward EXPANSION Ailaoshan-red river shear zone TIBETAN PLATEAU
下载PDF
Effect of Reduction Temperature on Hydrofining Performance of Supported Molybdenum Phosphide Catalyst
3
作者 Fengyan Li zhifang zhao +3 位作者 Qingjie Li Tianbo zhao Cuiqing Li Guida Sun 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2005年第4期233-237,共5页
A series of supported molybdenum phosphide catalysts were prepared by impregnation method. XRD, TG-DTG, XPS and BET were used to study the phase, compositions and surface areas of the prepared catalysts. A model react... A series of supported molybdenum phosphide catalysts were prepared by impregnation method. XRD, TG-DTG, XPS and BET were used to study the phase, compositions and surface areas of the prepared catalysts. A model reactant containing thiophene, pyridine and cyclohexene was used for the measurements of catalytic activities. The effect of reduction temperature on catalytic activities was investigated. The analysis results by XRD and BET are very different when the reduction temperature is changed from 400 to 900 ℃. MoP/γ-Al2O3 catalysts and CoMoP/γ-Al2O3 catalysts prepared at the reduction temperature of 500 ℃ are the most active ones. 展开更多
关键词 molybdenum phosphide reduction temperature HYDRODENITROGENATION HYDRODESULFURIZATION supported catalyst
下载PDF
慢性乙型肝炎患者肠道菌群与肝脏生化指标的相关性 被引量:11
4
作者 赵志方 秦松 +4 位作者 王莉 李莉莉 刘友德 邓丽霞 邹志强 《生物工程学报》 CAS CSCD 北大核心 2021年第1期301-311,共11页
乙型肝炎病毒感染引起的慢性乙型肝炎(Chronic hepatitis B,CHB)是一种全球性流行疾病,严重时可引起肝功能衰竭,甚至发展成肝硬化和肝癌。也已发现CHB的发生和发展与肠道菌群的组成和结构的变化密切相关。为进一步探究肠道菌群结构与肝... 乙型肝炎病毒感染引起的慢性乙型肝炎(Chronic hepatitis B,CHB)是一种全球性流行疾病,严重时可引起肝功能衰竭,甚至发展成肝硬化和肝癌。也已发现CHB的发生和发展与肠道菌群的组成和结构的变化密切相关。为进一步探究肠道菌群结构与肝脏生化指标之间的联系,文中随机纳入14名CHB患者和11名健康对照者(Control group,CN),分析其肝脏生化指标和肠道菌群的结构以及两者的相关性。结果发现CHB患者肝脏生化指标丙氨酸转氨酶(Alanine transaminase,ALT)、总胆红素(Total bilirubin,TBIL)和γ-谷氨酰转移酶(Gamma glutamyl transferase,GGT)等的水平发生显著变化;普雷沃氏菌属Prevotella、劳特氏菌属Blautia、瘤胃球菌属Ruminococcus、Eubacterium eligens group等菌属失调;单形拟杆菌Bacteroides uniformis和Ruminococcus sp.5139BFAA可能与CHB患者的肝损伤相关,提示这些菌可能成为治疗CHB的新"切入点"。 展开更多
关键词 慢性乙型肝炎 肠道菌群 16S rRNA 肝脏生化指标
原文传递
U-Pb Geochronology, Elemental and Sr-Nd Isotopic Geochemistry of the Houyaoyu Granite Porphyries: Implication for the Genesis of Early Cretaceous Felsic Intrusions in East Qinling 被引量:7
5
作者 Xiaohu He Hong Zhong +6 位作者 zhifang zhao Shucheng Tan Weiguang Zhu Siqi Yang Wenjun Hu Zhong Tang Congfa Bao 《Journal of Earth Science》 SCIE CAS CSCD 2018年第4期920-938,共19页
The Early Cretaceous Houyaoyu granite porphyries are located in the south margin of the North China Craton. Field observations, petrography, geochronology, major and trace elemental and Sr-Nd isotopic compositions are... The Early Cretaceous Houyaoyu granite porphyries are located in the south margin of the North China Craton. Field observations, petrography, geochronology, major and trace elemental and Sr-Nd isotopic compositions are reported to elucidate the genesis of the Houyaoyu granite porphyries. SIMS zircon U-Pb analyses for the Houyaoyu granite porphyries yield two concordant ages of 133.2±2.3 (2σ) and 131±1.1 (2σ) Ma, respectively. Major and trace elemental compositions indicate that these porphyries are high-K I-type granites with high contents of SiO2, K20, Rb, U, Pb, low Nb, Ta, Ti, and P. Initial S:Sr/S6Sr ratios range from 0.708 3 to 0.709 7, and εNd(t) values range from -9.13 to -12.3, with corresponding two-stage depleted-mantie Nd model ages (T2DM) varying from 1.57 to 1.91 Ga. This suggests that the Houyaoyu granite porphyries were predominantly derived from ancient lower conti- nental crust, with minor involvement of mantie-derived components. On the basis of the tectonic evolution of the Qinling Orogen and geochemical characteristics of the Houyaoyu granite porphyries, it is proposed that they were formed in an extensional tectonic setting related to lithospheric destruction of the North China Craton, and produced Mo and Pb-Zn mineralization in East Qinling Orogen. KEY WORDS: East Qinling, granite porphyries, ancient lower continental crust, destruction of North China Craton. 展开更多
关键词 East Qinling granite porphyries ancient lower continental crust destruction of NorthChina Craton.
原文传递
How a single receptor‑like kinase exerts diverse roles:lessons from FERONIA
6
作者 Gaopeng Wang zhifang zhao +2 位作者 Xinhang Zheng Wenfeng Shan Jiangbo Fan 《Molecular Horticulture》 2022年第1期307-317,共11页
FERONIA(FER)is a member of the Catharanthus roseus receptor-like kinase 1-like(CrRLK1L)protein subfamily,which participates in reproduction,abiotic stress,biotic stress,cell growth,hormone response,and other molecular... FERONIA(FER)is a member of the Catharanthus roseus receptor-like kinase 1-like(CrRLK1L)protein subfamily,which participates in reproduction,abiotic stress,biotic stress,cell growth,hormone response,and other molecular mecha-nisms of plants.However,the mechanism by which a single RLK is capable of mediating multiple signals and activat-ing multiple cellular responses remains unclear.Here,we summarize research progress revealing the spatial–temporal expression of FER,along with its co-receptors and ligands determined the function of FER signaling pathway in multiple organs.The specificity of the FER signaling pathway is proposed to operate under a four-layered mechanism:(1)Spatial–temporal expression of FER,co-receptors,and ligands specify diverse functions,(2)Specific ligands or ligand combinations trigger variable FER signaling pathways,(3)Diverse co-receptors confer diverse FER perception and response modes,and(4)Unique downstream components that modify FER signaling and responses.Moreover,the regulation mechanism of the signaling pathway-appears to depend on the interaction among the ligands,RLK receptors,co-receptors,and downstream components,which may be a general mechanism of RLKs to maintain signal specificity.This review will provide a insight into understanding the specificity determination of RLKs signaling in both model and horticultural crops. 展开更多
关键词 FERONIA Signaling pathway Regulation mechanism IMMUNITY Cell growth
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部