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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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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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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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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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TIN2015-65515-C4-1-R) A preliminary version was presented at the 13th International

JULIAN,C. CARRASCOSA

《信息与电子工程前沿（英文）》 2016年 第17卷 第4期   页码 325-337 doi: 10.1631/FITEE.1500343

摘要： Human-agent societies refer to applications where virtual agents and humans coexist and interact transparently into a fully integrated environment. One of the most important aspects in this kind of applications is including emotional states of the agents (humans or not) in the decision-making process. In this sense, this paper presents the applicability of the JaCalIVE (Jason Cartago implemented intelligent virtual environment) framework for developing this kind of society. Specifically, the paper presents an ambient intelligence application where humans are immersed into a system that extracts and analyzes the emotional state of a human group. A social emotional model is employed to try to maximize the welfare of those humans by playing the most appropriate music in every moment.

关键词： Multi-agent systems     Virtual environments     Emotional agents    

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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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TIN2012-34003 and TIN2013-47074-C2-1-R) and FPU Scholarship (FPU13/03141) from the Spanish Government A preliminary version was presented at the 13th International Conference on Practical

Miguel OLIVER,Francisco MONTERO,José Pascual MOLINA,Pascual GONZÁLEZ,Antonio FERNÁNDEZ-CABALLERO

《信息与电子工程前沿（英文）》 2016年 第17卷 第4期   页码 348-364 doi: 10.1631/FITEE.1500347

摘要： This paper seeks to determine how the overlap of several infrared beams affects the tracked position of the user, depending on the angle of incidence of light, distance to the target, distance between sensors, and the number of capture devices used. We also try to show that under ideal conditions using several Kinect sensors increases the precision of the data collected. The results obtained can be used in the design of telerehabilitation environments in which several RGB-D cameras are needed to improve precision or increase the tracking range. A numerical analysis of the results is included and comparisons are made with the results of other studies. Finally, we describe a system that implements intelligent methods for the rehabilitation of patients based on the results of the tests carried out.

关键词： Kinect sensor     Rehabilitation system     Capture precision     Multi-camera system    

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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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RESPONSE OF WHEAT COMPOSITE CROSS POPULATIONS TO DISEASE AND CLIMATE VARIATION OVER 13 GENERATIONS

《农业科学与工程前沿（英文）》 2021年 第8卷 第3期   页码 400-415 doi: 10.15302/J-FASE-2021394

摘要：

Since the F5 (2005), three winter wheat composite cross populations (CCPs) based on germplasm specifically suitable for low-input conditions were subjected to natural selection under organic and conventional management. In the F6, each CCP was divided into two parallel populations (12 CCPs in total) and maintained continuously until 2018. Commonly used modern cultivars with different disease susceptibilities were grown alongside to assess the agronomic performance of the CCPs. The organically managed CCPs were comparable in yield and foliar disease resistance to two continuously used reference cultivars, Achat and Capo. In contrast, under conventional management the cv. Capo outyielded the CCPs (Achat was not tested), highlighting the importance of parental cultivar choice for specific management systems. The CCPs were found to be moderately resistant to brown rust and even to the newly emerged stripe rust races prevalent in Europe since 2011. Differences between the CCPs were mainly due to parental genetic background and were significant in the first five generations, but were no longer so in the last five generations. In addition, these differences tended to vary depending on the experimental year and the environmental stresses present. In conclusion, the CCPs despite being derived from older cultivars are able to compete with more recently released reference cultivars under organic farming practices and represent a dynamic germplasm resource.

 

关键词： evolutionary breeding     heterogeneous crop population     management system    

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Symbiotic performance, shoot biomass and water-use efficiency of three groundnut (

Sofiya K. MUHABA, Felix D. DAKORA

《农业科学与工程前沿（英文）》 2020年 第7卷 第4期   页码 455-466 doi: 10.15302/J-FASE-2020354

摘要：

Phosphorus is a key nutrient element involved in energy transfer for cellular metabolism, respiration and photosynthesis and its supply at low levels can affect legume nodulation, N fixation, and C assimilation. A two-year field study was conducted in Ethiopia in 2012 and 2013 to evaluate the effects of P supply on growth, symbiotic N nutrition, grain yield and water-use efficiency of three groundnut genotypes. Supplying P to the genotypes significantly increased their shoot biomass, symbiotic performance, grain yield, and C accumulation. There was, however, no effect on shoot δ C values in either year. Compared to the zero-P control, supplying 40 kg·ha P markedly increased shoot biomass by 77% and 66% in 2012 and 2013, respectively. In both years, groundnut grain yields were much higher at 20 and 30 kg·ha P. Phosphorus supply markedly reduced shoot δ N values and increased the %Ndfa and amount of N-fixed, indicating the direct involvement of P in promoting N fixation in nodulated groundnut. The three genotypes differed significantly in δ N, %Ndfa, N-fixed, grain yield, C concentration, and δ C. The phosphorus × genotype interaction was also significant for shoot DM, N content, N-fixed and soil N uptake.

关键词： shoot yield     N-fixed     %Ndfa     δ15N     δ13C     water-use efficiency    

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FGF13 suppresses acute myeloid leukemia by regulating bone marrow niches

《医学前沿（英文）》 2022年 第16卷 第6期   页码 896-908 doi: 10.1007/s11684-022-0944-z

摘要： Fibroblast growth factor 13 (FGF13) is aberrantly expressed in multiple cancer types, suggesting its essential role in tumorigenesis. Hence, we aimed to explore its definite role in the development of acute myeloid leukemia (AML) and emphasize its associations with bone marrow niches. Results showed that FGF13 was lowly expressed in patients with AML and that its elevated expression was related to prolonged overall survival (OS). Univariate and multivariate Cox regression analyses identified FGF13 as an independent prognostic factor. A prognostic nomogram integrating FGF13 and clinicopathologic variables was constructed to predict 1-, 3-, and 5-year OS. Gene mutation and functional analyses indicated that FGF13 was not associated with AML driver mutations but was related to bone marrow niches. As for immunity, FGF13 was remarkably associated with T cell count, immune checkpoint genes, and cytokines. In addition, FGF13 overexpression substantially inhibited the growth and significantly induced the early apoptosis of AML cells. The xenograft study indicated that FGF13 overexpression prolonged the survival of recipient mice. Overall, FGF13 could serve as an independent prognostic factor for AML, and it was closely related to the bone marrow microenvironment.

关键词： acute myeloid leukemia     FGF13     prognosis     immune-related genes     bone marrow niches    

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Human health ambient water quality criteria for 13 heavy metals and health risk assessment in Taihu Lake

《环境科学与工程前沿（英文）》 2022年 第16卷 第4期 doi: 10.1007/s11783-021-1475-6

摘要：

• The concentrations of 13 heavy metals in Taihu Lake were analyzed.

关键词： Heavy metals     Human health ambient water quality criteria     Taihu Lake     Health risk assessment     Contribution rate    

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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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Low-temperature CO oxidation over Au-doped 13X-type zeolite catalysts: preparation and catalytic activity

Qing YE, Donghui LI, Jun ZHAO, Jiansheng ZHAO, Tianfang KANG, Shuiyuan CHENG

《环境科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 497-504 doi: 10.1007/s11783-011-0256-z

摘要： Au-supported 13X-type zeolite (Au/13X) was synthesized using a common deposition–precipitation (DP) method with a solution of sodium carbonate as a precipitate agent. Further testing was conducted to test for catalytic oxidation of CO. A study was conducted on the effects of different preparation conditions (i.e., chloroauric acid concentration, solution temperature, pH of solution, and calcinations temperature) on Au/13X for CO oxidation. In respect to the catalytic activity, the relationship between different the preparation conditions and gold particles in 13X zeolite was analyzed using X-ray diffraction, TEM and XPS. The activity of Au/13X catalysts in CO oxidation was dependent on the chloroauric acid concentration. From XRD results, a higher chloroauric acid concentration induced larger gold nanoparticles, which resulted in lower catalytic activity. Results revealed that higher temperatures induced higher Au loading, homogeneous deposit, and smaller gold clusters on the support of 13X, resulting in higher CO activity. Furthermore, a pH of 5 or 6 generated greater amounts of Au loading and smaller Au particles on 13X than at a pH of 8 or 9. This may be a result of an effective exchange between and Au(OH) Cl on specific surface sites of zeolite under the pH’s 5 and 6. The sample calcined at 300°C showed the highest activity, which may be due to the sample’s calcined at 200°C inability to decompose completely to metallic gold while the sample calcined at 400°C had larger particles of gold deposited on the support. It can be concluded from this study that Au/13X prepared from a gold solution with an initial chloroauric acid solution concentration of 1.5 × 10 mol·L gold solution pH of 6, solution temperature of around 90°C, and a calcination temperature of 300°C provides optimum catalytic activity for CO oxidation.

关键词： 13X-type zeolite     CO oxidation     gold solution     pH     calcination temperature    

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Prevalence of asthma symptoms in Golestan schoolchildren aged 6–7 and 13–14 years in Northeast Iran

null

《医学前沿（英文）》 2016年 第10卷 第3期   页码 345-350 doi: 10.1007/s11684-016-0462-y

摘要：

Asthma is the most common chronic disease among children, and its incidences are often imminent among elementary schoolchildren. This study aimed to examine the prevalence of asthma symptoms in Golestan schoolchildren aged 6–7 and 13–14 years in Northeast Iran. The prevalence rate was compared according to age group (aged 6–7 years vs. aged 13–14 years) and gender (male vs. female). In this cross-sectional study, 1706 Iranian schoolchildren aged 6–7 and 13–14 years in Golestan Province were enrolled. Participants completed questionnaires between February and July 2014. Asthma symptoms were assessed using the questionnaire of the International Study of Asthma and Allergies in Childhood protocol in Persian. The logistic regression model was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of the asthma symptoms for each of the gender and age groups. The prevalence rates of “current asthma” symptoms and “asthma ever” in all the children were estimated as 9.5% and 7.5%, respectively. The prevalence of asthma (“asthma ever” and “wheezing in the past 12 months”) in junior high schoolchildren (aged 13–14 years) is higher than that in elementary schoolchildren (aged 6–7 years) (P <0.05). The prevalence of the severity of wheezing in girls is lower than that in boys (OR= 1.7, 95%CI= 1.06–2.96, P = 0.02). Asthma is still a major public health problem. This study shows that the prevalence of the asthma symptoms in boys is lower than that in girls in both age groups, and the severity of asthma in girls is higher than that in boys aged 13–14 years.

关键词： asthma     asthma symptoms     epidemiology     childhood     chronic disease    

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标题 作者 时间 类型 操作

Precipitation study of CO

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

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

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

Progress in NMR-based metabolomics of

Qifang PAN,Jingya ZHAO,Yuliang WANG,Kexuan TANG

期刊论文

TIN2015-65515-C4-1-R) A preliminary version was presented at the 13th International

JULIAN,C. CARRASCOSA

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

TIN2012-34003 and TIN2013-47074-C2-1-R) and FPU Scholarship (FPU13/03141) from the Spanish Government A preliminary version was presented at the 13th International Conference on Practical

Miguel OLIVER,Francisco MONTERO,José Pascual MOLINA,Pascual GONZÁLEZ,Antonio FERNÁNDEZ-CABALLERO

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

RESPONSE OF WHEAT COMPOSITE CROSS POPULATIONS TO DISEASE AND CLIMATE VARIATION OVER 13 GENERATIONS

期刊论文

Symbiotic performance, shoot biomass and water-use efficiency of three groundnut (

Sofiya K. MUHABA, Felix D. DAKORA

期刊论文

FGF13 suppresses acute myeloid leukemia by regulating bone marrow niches

期刊论文

Human health ambient water quality criteria for 13 heavy metals and health risk assessment in Taihu Lake

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

Low-temperature CO oxidation over Au-doped 13X-type zeolite catalysts: preparation and catalytic activity

Qing YE, Donghui LI, Jun ZHAO, Jiansheng ZHAO, Tianfang KANG, Shuiyuan CHENG

期刊论文

Prevalence of asthma symptoms in Golestan schoolchildren aged 6–7 and 13–14 years in Northeast Iran

null

期刊论文