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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    

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    

Effect of noble metal nanoparticle size on C–N bond cleavage performance in hydrodenitrogenation: a study

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 1986-2000 doi: 10.1007/s11705-023-2337-5

摘要: Breakage of the C–N bond is a structure sensitive process, and the catalyst size significantly affects its activity. On the active metal nanoparticle scale, the role of catalyst size in C–N bond cleavage has not been clearly elucidated. So, Ru catalysts with variable nanoparticle sizes were obtained by modulating the reduction temperature, and the catalytic activity was evaluated using 1,2,3,4-tetrahydroquinoline and o-propylaniline with different C–N bond hybridization patterns as reactants. Results showed a 13 times higher reaction rate for sp3-hybridized C–N bond cleavage than sp2-hybridized C–N bond cleavage, while the reaction rate tended to increase first and then decrease as the catalyst nanoparticle size increased. Different concentrations of terrace, step, and corner sites were found in different sizes of Ru nanoparticles. The relationship between catalytic site variation and C–N bond cleavage activity was further investigated by calculating the turnover frequency values for each site. This analysis indicates that the variation of different sites on the catalyst is the intrinsic factor of the size dependence of C–N bond cleavage activity, and the step atoms are the active sites for the C–N bond cleavage. When Ru nanoparticles are smaller than 1.9 nm, they have a strong adsorption effect on the reactants, which will affect the catalytic performance of the Ru catalyst. Furthermore, these findings were also confirmed on other metallic Pd/Pt catalysts. The role of step sites in C–N bond cleavage was proposed using the density function theory calculations. The reactants have stronger adsorption energies on the step atoms, and step atoms have d-band center nearer to the Fermi level. In this case, the interaction with the reactant is stronger, which is beneficial for activating the C–N bond of the reactant.

关键词: sp3/sp2-hybridized C–N bond     noble metal nanoparticle     catalytic active site     turnover frequency     DFT    

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    

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.    

动态二叉树表示环境的A<sup>*sup>算法及其在足球机器人路径规划中的实现

唐平,杨宜民

《中国工程科学》 2002年 第4卷 第9期   页码 50-53

摘要:

提出采用二叉树表示二维空间的方法,对全局路径规划和局部路径规划进行综合考虑,设计移动机器人在复杂环境下对动态障碍物进行避障的A<sup>*sup>算法。

关键词: 动态二叉树     A<sup>*sup>算法     路径规划    

Clinical significance of CD34<sup>+sup>CD117<sup>dimsup>/CD34<sup>+sup>CD117<sup>brisup> myeloblast-associated

Xueping Li, Yuting Dai, Bing Chen, Jinyan Huang, Saijuan Chen, Lu Jiang

《医学前沿(英文)》 2021年 第15卷 第4期   页码 608-620 doi: 10.1007/s11684-021-0836-7

摘要: t(8;21)(q22;q22) acute myeloid leukemia (AML) is a highly heterogeneous hematological malignancy with a high relapse rate in China. Two leukemic myeloblast populations (CD34 CD117 and CD34 CD117 ) were previously identified in t(8;21) AML, and CD34 CD117 cell proportion was determined as an independent factor for this disease outcome. Here, we examined the impact of CD34 CD117 /CD34 CD117 myeloblast-associated gene expression on t(8;21) AML clinical prognosis. In this study, 85 patients with t(8;21) AML were enrolled. The mRNA expression levels of CD34 CD117 -associated genes ( , , and ) and CD34 CD117 -associated genes ( , , and ) were measured using quantitative reverse transcription PCR. Associations between gene expression and clinical outcomes were determined using Cox regression models. Results showed that patients with high , , or expression had significantly inferior overall survival (OS), whereas those with high or expression showed relatively favorable prognosis. Univariate analysis revealed that CD19, CD34 CD117 proportion, mutation, minimal residual disease (MRD), and expression levels of , , , and were associated with OS. Multivariate analysis indicated that mutation, MRD and and expression levels were independent prognostic variables for OS. Identifying the clinical relevance of CD34 CD117 /CD34 CD117 myeloblast-associated gene expression may provide new clinically prognostic markers for t(8;21) AML.

关键词: t(8     21)(q22     q22) AML     CD34+CD117dim/ CD34+CD117bri cell population     gene expression     prognosis    

K<sup>+sup> and Na<sup>+sup> fluxes in roots of two Chinese Iris populations

Pinfang LI,Biao ZHANG

《农业科学与工程前沿(英文)》 2014年 第1卷 第2期   页码 144-149 doi: 10.15302/J-FASE-2014016

摘要: Maintenance of ion homeostasis, particularly the regulation of K and Na uptake, is important for all plants to adapt to salinity. Observations on ionic response to salinity and net fluxes of K , Na in the root exhibited by plants during salt stress have highlighted the need for further investigation. The objectives of this study were to compare salt adaptation of two Chinese Iris ( Pall. var. (Fisch.) Koidz.) populations, and to improve understanding of adaptation to salinity exhibited by plants. Plants used in this study were grown from seeds collected in the Xinjiang Uygur Autonomous Region (Xj) and Beijing Municipality (Bj), China. Hydroponically-grown seedlings of the two populations were supplied with nutrient solutions containing 0.1 (control) and 140 mmol·L NaCl. After 12 days, plants were harvested for determination of relative growth rate and K , Na concentrations. Net fluxes of K , Na from the apex and along the root axis to 10.8 mm were measured using non-invasive micro-test technique. With 140 mmol·L NaCl treatment, shoots for population Xj had larger relative growth rate and higher K concentration than shoots for population Bj. However, the Na concentrations in both shoots and roots were lower for Xj than those for Bj. There was a lower net efflux of K found in population Xj than by Bj in the mature zone (approximately 2.4-10.8 mm from root tip). However, no difference in the efflux of Na between the populations was obtained. Population Xj of continued to grow normally under NaCl stress, and maintained a higher K /Na ratio in the shoots. These traits, which were associated with lower K leakage, help population Xj adapt to saline environments.

关键词: Iris lactea Pall. var. chinensis (Fisch.) Koidz     population     K+ and Na+     ion flux     non-invasive micro-test technique    

An electrochemical process that uses an Fe

Chaojie Jiang, Lifen Liu, John C. Crittenden

《环境科学与工程前沿(英文)》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0860-z

摘要: A bio-electrochemical fuel cell reactor with cathodic Fe /TiO generates electricity. It destroys recalcitrant pollutants in cathode chamber without photocatalysis. Fe /TiO generates reactive oxygenated species in the dark or under photocatalysis. Cathodic produced ROS (hydroxy radical/superoxide radical) can degrade tetracycline or dyes. Electricity generation is enhanced by semiconductor catalyzed cathodic degradation of pollutants. In this study, a new water treatment system that couples (photo-) electrochemical catalysis (PEC or EC) in a microbial fuel cell (MFC) was configured using a stainless-steel (SS) cathode coated with Fe /TiO . We examined the destruction of methylene blue (MB) and tetracycline. Fe /TiO was prepared using a chemical reduction-deposition method and coated onto an SS wire mesh (500 mesh) using a sol technique. The anode generates electricity using microbes (bio-anode). Connected via wire and ohmic resistance, the system requires a short reaction time and operates at a low cost by effectively removing 94% MB (initial concentration 20 mg·L ) and 83% TOC/TOC under visible light illumination (50 W; 1.99 mW·cm for 120 min, MFC-PEC). The removal was similar even without light irradiation (MFC-EC). The of the MFC-PEC system was approximately 0.675 kWh·m ·order , whereas that of the MFC-EC system was zero. The system was able to remove 70% COD in tetracycline solution (initial tetracycline concentration 100 mg·L ) after 120 min of visible light illumination; without light, the removal was 15% lower. The destruction of MB and tetracycline in both traditional photocatalysis and photoelectrocatalysis systems was notably low. The electron spin-resonance spectroscopy (ESR) study demonstrated that ·OH was formed under visible light, and ·O was formed without light. The bio-electricity-activated O and ROS (reactive oxidizing species) generation by Fe /TiO effectively degraded the pollutants. This cathodic degradation improved the electricity generation by accepting and consuming more electrons from the bio-anode.

关键词: Bio-anode     Photocatalytic cathode     Fe0/TiO2     ESR     Dye and antibiotics     Advanced oxidation    

Application of Fe

Xiaowei ZHANG,Qinyan YUE,Dongting YUE,Baoyu GAO,Xiaojuan WANG

《环境科学与工程前沿(英文)》 2015年 第9卷 第3期   页码 402-410 doi: 10.1007/s11783-014-0659-8

摘要: Dyes are common pollutants in textile wastewaters, and the treatment of the wastewater has now attracted much attention due to its wide application and low biodegradability. In this study, Fe /C/Clay ceramics, a kind of novel micro-electrolysis filler, were sintered and employed in a dynamic micro-electrolysis reactor for synthetic Acid Red 73 (AR73) and Reactive Blue 4 (RB4) wastewater treatment. The effects of influent pH, hydraulic retention time (HRT), and aeration on the decoloration efficiencies of AR73 and RB4 were studied. The optimum conditions for wastewater treatment were: AR73, influent pH of 4, HRT of 2 h and aeration; RB4, influent pH of 5, HRT of 6 h and aeration. Under the optimum conditions, decoloration efficiency of AR73 and RB4 wastewater was 96% and 83%, respectively. Results of UV-vis spectrum scanning demonstrated that the chromophores were broken. Continuous running tests showed that improvement of micro-electrolysis system with Fe /C/Clay ceramics for AR73 and RB4 synthetic wastewater treatment could avoid failure of micro-electrolysis reactor, which indicated great potential for the practical application of the ceramics in the field of actual industrial wastewater treatment.

关键词: Fe0/C/Clay ceramics     micro-electrolysis     Acid Red 73     Reactive Blue 4     synthetic wastewater    

Removal of ammonium and nitrate through Anammox and FeS-driven autotrophic denitrification

《环境科学与工程前沿(英文)》 2023年 第17卷 第6期 doi: 10.1007/s11783-023-1674-4

摘要:

● Simultaneous NH4+/NO3 removal was achieved in the FeS denitrification system

关键词: Anammox     Denitrification     FeS     NH4+/NO3     Sulfammox    

Selective recovery of Cu

Haiping LUO,Bangyu QIN,Guangli LIU,Renduo ZHANG,Yabo TANG,Yanping HOU

《环境科学与工程前沿(英文)》 2015年 第9卷 第3期   页码 522-527 doi: 10.1007/s11783-014-0633-5

摘要: As the bioelectrochemical system, the microbial fuel cell (MFC) and the microbial electrolysis cell (MEC) were developed to selectively recover Cu and Ni ions from wastewater. The wastewater was treated in the cathode chambers of the system, in which Cu and Ni ions were removed by using the MFC and the MEC, respectively. At an initial Cu concentration of 500 mg·L , removal efficiencies of Cu increased from 97.0%±1.8% to 99.0%±0.3% with the initial Ni concentrations from 250 to 1000 mg·L , and maximum power densities increased from 3.1±0.5 to 5.4±0.6 W·m . The Ni removal mass in the MEC increased from 6.8±0.2 to 20.5±1.5 mg with the increase of Ni concentrations. At an initial Ni concentration of 500 mg·L , Cu removal efficiencies decreased from 99.1%±0.3% to 74.2%±3.8% with the initial Cu concentrations from 250 to 1000 mg·L , and maximum power densities increased from 3.0±0.1 to 6.3±1.2 W·m . Subsequently, the Ni removal efficiencies decreased from 96.9%±3.1% to 73.3%±5.4%. The results clearly demonstrated the feasibility of selective recovery of Cu and Ni from the wastewater using the bioelectrochemical system.

关键词: bioelectrochemical system     Cu2+     Ni2+     selective recovery    

Advances of 12<sup>thsup> CAPS research symposium: young chemists and chemical engineers fronts

Guoping Hu, Baiqian Dai

《化学科学与工程前沿(英文)》 2021年 第15卷 第3期   页码 461-463 doi: 10.1007/s11705-020-2026-6

Effects of ancillary ligands in acceptorless benzyl alcohol dehydrogenation mediated by phosphine-free cobalt complexes

《化学科学与工程前沿(英文)》 2023年 第17卷 第3期   页码 314-325 doi: 10.1007/s11705-022-2219-2

摘要: Acceptorless alcohol dehydrogenation stands out as one of the most promising strategies in hydrogen storage technologies. Among various catalytic systems for this reaction, cost-effective molecular catalysts using phosphine-free ligands have gained considerable attention. However, the central challenge for using non-precious metals is to overcome the propensity of reacting by one-electron pathway. Herein, we synthesized a phosphine-free η5-C5Me5-Co complex by using the metal–ligand cooperative strategy and compared its activity with analogous catalysts toward acceptorless alcohol dehydrogenation. The catalyst showed excellent performance with a turnover number of 130.4 and a selectivity close to 100%. The improved performance among the class of η5-C5Me5-Co complexes could be attributed to the more accessible Co center and its cooperation with the redox-active ligand. To further study the systematic structure-activity relationship, we investigated the electronic structures of η5-C5Me5-Co complexes by a set of characterizations. The results showed that the redox-active ligand has a significant influence on the η5-C5Me5-Co moiety. In the meantime, the proximal O/OH group is beneficial for shuttling protons. For the catalytic cycle, two dehydrogenation scenarios were interrogated through density functional theory, and the result suggested that the outer-sphere pathway was preferred. The formation of a dihydrogen complex was the rate-determining step with a ΔG value of 16.9 kcal∙mol‒1. The electron population demonstrated that the η5-C5Me5 ligand played a key role in stabilizing transition states during dehydrogenation steps. This work identified the roles of vital ligand components to boost catalytic performance and offered rationales for designing metal–ligand cooperative nonprecious metal complexes.

关键词: acceptorless alcohol dehydrogenation     η5-C5Me5-Co     metal–ligand cooperation     theoretical calculation    

RNA m<sup>6sup>A modification and its function in diseases

null

《医学前沿(英文)》 2018年 第12卷 第4期   页码 481-489 doi: 10.1007/s11684-018-0654-8

摘要:

N6-methyladenosine (m6A) is the most common post-transcriptional RNA modification throughout the transcriptome, affecting fundamental aspects of RNA metabolism. m6A modification could be installed by m6A “writers” composed of core catalytic components (METTL3/METTL14/WTAP) and newly defined regulators and removed by m6A “erasers” (FTO and ALKBH5). The function of m6A is executed by m6A “readers” that bind to m6A directly (YTH domain-containing proteins, eIF3 and IGF2BPs) or indirectly (HNRNPA2B1). In the past few years, advances in m6A modulators (“writers,” “erasers,” and “readers”) have remarkably renewed our understanding of the function and regulation of m6A in different cells under normal or disease conditions. However, the mechanism and the regulatory network of m6A are still largely unknown. Moreover, investigations of the m6A physiological roles in human diseases are limited. In this review, we summarize the recent advances in m6A research and highlight the functional relevance and importance of m6A modification in in vitro cell lines, in physiological contexts, and in cancers.

关键词: RNA modification     m6A     immunity     cancer     epigenetics    

标题 作者 时间 类型 操作

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

Sofiya K. MUHABA, Felix D. DAKORA

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

Effect of noble metal nanoparticle size on C–N bond cleavage performance in hydrodenitrogenation: a study

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

动态二叉树表示环境的A<sup>*sup>算法及其在足球机器人路径规划中的实现

唐平,杨宜民

期刊论文

Clinical significance of CD34<sup>+sup>CD117<sup>dimsup>/CD34<sup>+sup>CD117<sup>brisup> myeloblast-associated

Xueping Li, Yuting Dai, Bing Chen, Jinyan Huang, Saijuan Chen, Lu Jiang

期刊论文

K<sup>+sup> and Na<sup>+sup> fluxes in roots of two Chinese Iris populations

Pinfang LI,Biao ZHANG

期刊论文

An electrochemical process that uses an Fe

Chaojie Jiang, Lifen Liu, John C. Crittenden

期刊论文

Application of Fe

Xiaowei ZHANG,Qinyan YUE,Dongting YUE,Baoyu GAO,Xiaojuan WANG

期刊论文

Removal of ammonium and nitrate through Anammox and FeS-driven autotrophic denitrification

期刊论文

Selective recovery of Cu

Haiping LUO,Bangyu QIN,Guangli LIU,Renduo ZHANG,Yabo TANG,Yanping HOU

期刊论文

Advances of 12<sup>thsup> CAPS research symposium: young chemists and chemical engineers fronts

Guoping Hu, Baiqian Dai

期刊论文

Effects of ancillary ligands in acceptorless benzyl alcohol dehydrogenation mediated by phosphine-free cobalt complexes

期刊论文

RNA m<sup>6sup>A modification and its function in diseases

null

期刊论文