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期刊论文 12

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中草药化学成分 1

创制新药 1

地层评价 1

天然产物 1

孔隙度 1

束缚水 1

核磁共振 1

波谱技术 1

测井 1

渗透率 1

高效色谱与核磁共振联用 1

高效色谱与质谱联用 1

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Progress in NMR-based metabolomics of

Qifang PAN,Jingya ZHAO,Yuliang WANG,Kexuan TANG

《农业科学与工程前沿（英文）》 2015年 第2卷 第3期   页码 195-204 doi: 10.15302/J-FASE-2015063

摘要： Metabolomics has been rapidly developed as an important field in plant sciences and natural products chemistry. As the only natural source for a diversity of monoterpenoid indole alkaloids (MIAs), especially the low-abundance antitumor agents vinblastine and vincristine, is highly valued and has been studied extensively as a model for medicinal plants improvement. Due to multistep enzymatic biosynthesis and complex regulation, genetic modification in the MIA pathway has resulted in complicated changes of both secondary and primary metabolism in , affecting not only the MIA pathway but also other pathways. Research at the metabolic level is necessary to increase knowledge on the genetic regulation of the whole metabolic network connected to MIA biosynthesis. Nuclear magnetic resonance (NMR) is a very suitable and powerful complementary technique for the identification and quantification of metabolites in the plant matrix. NMR-based metabolomics has been used in studies of for pathway elucidation, understanding stress responses, classification among different cultivars, safety and quality controls of transgenic plants, cross talk between pathways, and diversion of carbon fluxes, with the aim of fully unravelling MIA biosynthesis, its regulation and the function of the alkaloids in the plant from a systems biology point of view.

关键词： Catharanthus roseus     monoterpenoid indole alkaloids     NMR     metabolomics    

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chloride diffusion coefficient and microstructure parameters in concrete: A comparative analysis using NMR

Yurong ZHANG, Shengxuan XU, Yanhong GAO, Jie GUO, Yinghui CAO, Junzhi ZHANG

《结构与土木工程前沿（英文）》 2020年 第14卷 第6期   页码 1509-1519 doi: 10.1007/s11709-020-0681-9

摘要： Permeability is a major indicator of concrete durability, and depends primarily on the microstructure characteristics of concrete, including its porosity and pore size distribution. In this study, a variety of concrete samples were prepared to investigate their microstructure characteristics via nuclear magnetic resonance (NMR), mercury intrusion porosimetry (MIP), and X-ray computed tomography (X-CT). Furthermore, the chloride diffusion coefficient of concrete was measured to explore its correlation with the microstructure of the concrete samples. Results show that the proportion of pores with diameters<1000 nm obtained by NMR exceeds that obtained by MIP, although the difference in the total porosity determined by both methods is minimal. X-CT measurements obtained a relatively small porosity; however, this likely reflects the distribution of large pores more accurately. A strong correlation is observed between the chloride diffusion coefficient and the porosity or contributive porosity of pores with sizes<1000 nm. Moreover, microstructure parameters measured via NMR reveal a lower correlation coefficient versus the chloride diffusion coefficient relative to the parameters determined via MIP, as NMR can measure non-connected as well as connected pores. In addition, when analyzing pores with sizes>50 µm, X-CT obtains the maximal contributive porosity, followed by MIP and NMR.

关键词： permeability     microstructure     NMR     MIP     X-CT    

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Solid-state NMR for metal-containing zeolites: From active sites to reaction mechanism

Xingling Zhao, Jun Xu, Feng Deng

《化学科学与工程前沿（英文）》 2020年 第14卷 第2期   页码 159-187 doi: 10.1007/s11705-019-1885-1

摘要： Metal-containing zeolite catalysts have found a wide range of applications in heterogeneous catalysis. To understand the nature of metal active sites and the reaction mechanism over such catalysts is of great importance for the establishment of structure-activity relationship. The advanced solid-state NMR (SSNMR) spectroscopy is robust in the study of zeolites and zeolite-catalyzed reactions. In this review, we summarize recent developments and applications of SSNMR for exploring the structure and property of active sites in metal-containing zeolites. Moreover, detailed information on host-guest interactions in the relevant zeolite catalysis obtained by SSNMR is also discussed. Finally, we highlight the mechanistic understanding of catalytic reactions on metal-containing zeolites based on the observation of key surface species and active intermediates.

关键词： metal-containing zeolites     solid-state NMR     active site     host-guest interaction     reaction mechanism    

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核磁共振在石油测井与地层油气评价中的应用

肖立志,谢然红

《中国工程科学》 2003年 第5卷 第9期   页码 87-94

摘要：

核磁共振（NMR）在石油测井和地层油气评价中已经得到应用，是当前地球物理勘探的前沿领域之一。介绍了NMR测井的测量原理、应用基础和地层信息的表达方式，并讨论了NMR测井的主要应用和实例。

关键词： 核磁共振     测井     地层评价     孔隙度     束缚水     渗透率    

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Precipitation study of CO

Siming Chen, Yue Wu, Geoffrey W. Stevens, Guoping Hu, Wenshou Sun, Kathryn A. Mumford

《化学科学与工程前沿（英文）》 2020年 第14卷 第3期   页码 415-424 doi: 10.1007/s11705-019-1882-4

摘要： Focused beam reflectance measurement (FBRM) and C nuclear magnetic resonance ( C NMR) analysis were used to study the precipitation process of CO -loaded potassium glycinate (KGLY) solutions at different CO loadings, during the addition of ethanol as an antisolvent at a rate of 10 mL·min . The volume ratio of ethanol added to the KGLY solution (3.0 mol·L , 340 mL) ranged from 0 to 3.0. Three solid-liquid-liquid phases were formed during the precipitation process. The FBRM results showed that the number of particles formed increased with CO loading and ethanol addition for CO -unsaturated KGLY solutions, whilst for CO -saturated KGLY solution it first increased then decreased to a stable value with ethanol addition. C NMR spectroscopic analysis showed that the crystals precipitated from the CO -unsaturated KGLY solutions consisted of glycine only, and the quantity crystallised increased with CO loading and ethanol addition. However, a complex mixture containing glycine, carbamate and potassium bicarbonate was precipitated from CO -saturated KGLY solution with the maximum precipitation percentages of 94.3%, 31.4% and 89.6%, respectively, at the ethanol volume fractions of 1.6, 2.5 and 2.3.

关键词： crystallization     precipitation     glycinate     FBRM     13C NMR    

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A review of measurement methods for peracetic acid (PAA)

Chen Cheng, Haodong Li, Jinling Wang, Hualin Wang, Xuejing Yang

《环境科学与工程前沿（英文）》 2020年 第14卷 第5期 doi: 10.1007/s11783-020-1266-5

摘要： Abstract • Physical and chemical properties and application of peracetic acid solution. • Determination method of high concentration peracetic acid. • Determination method of residual peracetic acid (low concentration). Peroxyacetic acid has been widely used in food, medical, and synthetic chemical fields for the past several decades. Recently, peroxyacetic acid has gradually become an effective alternative disinfectant in wastewater disinfection and has strong redox capacity for removing micro-pollutants from drinking water. However, commercial peroxyacetic acid solutions are primarily multi-component mixtures of peroxyacetic acid, acetic acid, hydrogen peroxide, and water. During the process of water treatment, peroxyacetic acid and hydrogen peroxide (H2O2) often coexist, which limits further investigation on the properties of peroxyacetic acid. Therefore, analytical methods need to achieve a certain level of selectivity, particularly when peroxyacetic acid and hydrogen peroxide coexist. This review summarizes the measurement and detection methods of peroxyacetic acid, comparing the principle, adaptability, and relative merits of these methods.

关键词： Peroxyacetic acid     Measurement methods     Titration     Colorimetric     Chromatography     NMR    

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Metabolomics in human type 2 diabetes research

null

《医学前沿（英文）》 2013年 第7卷 第1期   页码 4-13 doi: 10.1007/s11684-013-0248-4

摘要：

The high prevalence of diabetes and diabetic complications has caused a huge burden on the modern society. Although scientific advances have led to effective strategies for preventing and treating diabetes over the past several decades, little progress has been made toward curing the disease or even getting it under control, from a public health and overall societal standpoint. There is still a lack of reliable biomarkers indicative of metabolic alterations associated with diabetes and different drug responses, highlighting the need for the development of early diagnostic and prognostic markers for diabetes and diabetic complications. The emergence of metabolomics has allowed researchers to systemically measure the small molecule metabolites, which are sensitive to the changes of both environmental and genetic factors and therefore, could be regarded as the link between genotypes and phenotypes. During the last decade, the progression made in metabolomics has provided insightful information on disease development and disease onset prediction. Recent studies using metabolomics approach coupled with statistical tools to predict incident diabetes revealed a number of metabolites that are significantly altered, including branched-chain and aromatic amino acids, such as isoleucine, leucine, valine, tyrosine and phenylalanine, as diagnostic or highly-significant predictors of future diabetes. This review summarizes the current findings of metabolomic studies in human investigations with the most common form of diabetes, type 2 diabetes.

关键词： metabolomics     type 2 diabetes     metabolic pathway     mass spectrometry     nuclear magnetic resonance (NMR)    

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G-quadruplex formation of oligonucleotides containing ALS and FTD related GGGGCC repeat

Jasna Brčić,Janez Plavec

《化学科学与工程前沿（英文）》 2016年 第10卷 第2期   页码 222-237 doi: 10.1007/s11705-016-1556-4

摘要： A largely increased number of GGGGCC repeats located in the non-coding region of gene have been identified as the leading cause of two related neurological disorders, familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). We examined G-quadruplex forming ability of GGGGCC-repeat containing oligonucleotides with four guanine tracts chosen as the smallest possible model to form a unimolecular G-quadruplex. These oligonucleotides are readily to folded into G-quadruplexes in the presence of K ions. However, the formation of multiple structures makes structural analysis challenging and time consuming. We observed that flanking sequences on 5'- and 3'-ends as well as mutations of loop residues have a profound effect on folding. Sequence d[(G C ) G ] was chosen for further scrutiny and optimization of nuclear magnetic resonance (NMR) spectroscopic properties with dG to 8Br-dG substitutions at specific positions in the sequence under different folding conditions. Expectedly, folding into desired predominant topology is facilitated when substituted residue adopted a conformation in the naturally-occurring structure. Single dG to 8Br-dG substitution at position 21 and fine tuning of folding conditions facilitate folding of d[(G C ) GG GG] into (mostly) a single G-quadruplex, and thus enable determination of its high-resolution structure by high-field NMR.

关键词： G-quadruplex     GGGGCC     NMR     ALS/FTD     polymorphism    

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从天然产物创制新药的发展趋势

于德泉

《中国工程科学》 1999年 第1卷 第2期   页码 87-90

摘要：

文章展望了从天然产物中创制新药的发展趋势。单味中草药有效成分的研究重点将转向瞄准质控的中药复方化学成分研究。进入21世纪，中国天然药物研究要在国际上占有重要位置，突破口便是中药复方现代化，其关键之一便是化学（有效）成分研究。从中草药中发现有效成分或先导物必须采用化学成分与生物活性研究融为一体的机制，采用高通量筛选，目标就是寻找有效成分或先导物进而创制新药。长短结合，正确处理知识创新和新药开发的关系。知识创新须体现在创制新药的应用基础研究中，是产生巨大效益的理论基础；短程开发是知识累积水平的体现，是科研经费的必要补充和保证。改革传统天然产物化学研究模式，实施以当代最先进大型谱仪为先导的天然产物研究战略。

关键词： 天然产物     创制新药     中草药化学成分     波谱技术     高效色谱与质谱联用     高效色谱与核磁共振联用    

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Solvability and thermal response of cellulose with different crystal configurations

Qian CHEN, Kai ZHENG, Qingtao FAN, Kun WANG, Haiyan YANG, Jianxin JIANG, Shijie LIU

《工程管理前沿（英文）》 2019年 第6卷 第1期   页码 62-69 doi: 10.1007/s42524-019-0001-z

摘要：

Cellulose is a biodegradable and renewable natural material that it is naturally resistant to breaking and modification. Moreover, the crystalline structure of cellulose is a major factor restricting its industrial utilization. In this study, cellulose polymorphs were prepared from natural cellulose, and their solvability and thermal response were investigated. Using liquid- and solid-state NMR signals, the distinct types and dissolving states of cellulose polymorphs were identified. The thermal behavior of the polymorphic forms of cellulose-d was also evaluated, and cellulose II exhibited the poorest thermal stability and a unique exothermic reaction.

关键词： cellulose     crystal structure     thermal response     XRD     CP/MAS 13C NMR    

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Influence of short chain ceramides and lipophilic penetration enhancers on the nano-structure of stratum corneum model membranes studied using neutron diffraction

Annett SCHROETER, Tanja ENGELBRECHT, Reinhard H. H. NEUBERT

《化学科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 29-36 doi: 10.1007/s11705-013-1302-0

摘要： Oriented stratum corneum model lipid membranes were used to study the influence of the short chain ceramides (CER)[NP] and [AP] as well as the impact of the lipophilic penetration enhancer molecules oleic acid (OA) and isopropyl myristate (IPM) on the lipid nanostructure. The influence of the enhancer molecules were studied using specifically deuterated OA and IPM and neutron diffraction. H NMR spectroscopy was used to study the impact of the ceramides’ degree of order within the stratum corneum model lipid membranes. It was found that CER[NP] forms two very stable phases with high resistance against temperature increase. Phase B showed unusual hydration behavior as no water uptake of this phase was observed. The H NMR spectroscopic measurements showed that CER[NP] based ternary model system had a higher state of lamellar order in comparison to CER[AP] based lipid matrix. The studies confirmed that the short chain ceramides, particularly CER[NP], have a very high impact on the integrity of the Stratum corneum lipid bilayers. The penetration enhancer OA has not influenced the repeat distance of the model membrane based on CER[AP], and was not able to induce a phase separation in the investigated lipid matrix. However, a disorder and a fluidisation of the model membranes were observed when OA was incorporated. IPM showed the same effect but two phases (assigned as phase A and B) appeared, when IPM was used as penetration enhancer and incorporated into the model membrane. Furthermore, two arrangements of IPM were identified in phase A using deuterated IPM. A model of the nanostructure of the Stratum corneum lipid membranes is presented.

关键词： nano-structure of the stratum corneum     ceramide     penetration enhancer     model membrane     neutron diffraction     2H NMR spectroscopy    

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Application and mechanism of polysaccharide extracted from Enteromorpha to remove nano-ZnO and humic acid in coagulation process

Jianzhang Sun, Baoyu Gao, Yuanxia Luo, Moxi Xue, Xing Xu, Qinyan Yue, Yan Wang

《环境科学与工程前沿（英文）》 2018年 第12卷 第3期 doi: 10.1007/s11783-018-1029-8

摘要： Enteromorpha polysaccharide (Ep) extracted from alga a novel green coagulant aid for nanoparticles (NPs) and heavy metal ions removal and the structure of EP was intensively studied in this study. The integration of Ep with polyaluminum chloride (PAC-Ep) coagulants exhibited higher coagulation performance than that of the polyaluminum chloride (PAC) because of the negatively charged NPs suspension and humic aid (HA) solution. Significant high removal efficiencies of dissolved organic matter (94.1%), turbidity (99.3%) and Zn ions (69.3%) were achieved by the PAC-Ep coagulants. The dual-coagulation properties of PAC-Ep for different pollutants was based on multiple mechanisms, including (i) Al charge neutralization; (ii) hydroxy aluminum hydroxyl bridging formed polynuclearhydroxy complexes bridge and sweep colloidal particles; (iii) adsorption and bridging of Ep chain for the NPs and heavy metal ions. Results indicated that the destabilization of colloid was induced by the coexisting HA and higher removal was achieved as ions adsorption was enhance in the presence of HA complexation. On the basis of that, the extraction of polysaccharide is a promising candidate for its high coagulation performance in water treatment.

关键词： Algal Extraction     Enteromorpha polysaccharide     1H-13C nuclear magnetic resonance (NMR)     Fourier transform infrared (FTIR)     X-ray photoelectron spectroscopy (XPS)     Coagulation mechanism.    

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标题 作者 时间 类型 操作

Progress in NMR-based metabolomics of

Qifang PAN,Jingya ZHAO,Yuliang WANG,Kexuan TANG

期刊论文

chloride diffusion coefficient and microstructure parameters in concrete: A comparative analysis using NMR

Yurong ZHANG, Shengxuan XU, Yanhong GAO, Jie GUO, Yinghui CAO, Junzhi ZHANG

期刊论文

Solid-state NMR for metal-containing zeolites: From active sites to reaction mechanism

Xingling Zhao, Jun Xu, Feng Deng

期刊论文

核磁共振在石油测井与地层油气评价中的应用

肖立志,谢然红

期刊论文

Precipitation study of CO

Siming Chen, Yue Wu, Geoffrey W. Stevens, Guoping Hu, Wenshou Sun, Kathryn A. Mumford

期刊论文

A review of measurement methods for peracetic acid (PAA)

Chen Cheng, Haodong Li, Jinling Wang, Hualin Wang, Xuejing Yang

期刊论文

Metabolomics in human type 2 diabetes research

null

期刊论文

G-quadruplex formation of oligonucleotides containing ALS and FTD related GGGGCC repeat

Jasna Brčić,Janez Plavec

期刊论文

从天然产物创制新药的发展趋势

于德泉

期刊论文

Solvability and thermal response of cellulose with different crystal configurations

Qian CHEN, Kai ZHENG, Qingtao FAN, Kun WANG, Haiyan YANG, Jianxin JIANG, Shijie LIU

期刊论文

Influence of short chain ceramides and lipophilic penetration enhancers on the nano-structure of stratum corneum model membranes studied using neutron diffraction

Annett SCHROETER, Tanja ENGELBRECHT, Reinhard H. H. NEUBERT

期刊论文

Application and mechanism of polysaccharide extracted from Enteromorpha to remove nano-ZnO and humic acid in coagulation process

Jianzhang Sun, Baoyu Gao, Yuanxia Luo, Moxi Xue, Xing Xu, Qinyan Yue, Yan Wang

期刊论文