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Effect of lime on speciation of heavy metals during composting of water hyacinth

Jiwan SINGH,Ajay S. KALAMDHAD

《环境科学与工程前沿(英文)》 2016年 第10卷 第1期   页码 93-102 doi: 10.1007/s11783-014-0704-7

摘要: Composting is attractive and inexpensive method for treatment and biomass disposal of water hyacinth. However, the major disadvantage of water hyacinth composting is the high content of heavy metals in the final compost. Addition of lime sludge significantly reduced most bioavailable fractions (exchangeable and carbonate) of heavy metals. Studies were carried on composting of water hyacinth ( ) with cattle manure and sawdust (6:3:1 ratio) and effects of addition of lime (1%, 2% and 3%) on heavy metal speciation were evaluated during 30 days of composting period. The Tessier sequential extraction method was employed to investigate the changes in speciation of heavy metals such as Zinc (Zn), Copper (Cu), Manganese (Mn), Iron (Fe), Lead (Pb), Nickel (Ni), Cadmium (Cd) and Chromium (Cr) during water hyacinth composting. Effects of physicochemical parameters such as temperature, pH and organic matter on speciation of heavy metals were also studied during the process. Results showed that, the total metal content was increased during the composting process. The higher reduction in bioavailability factor (BF) of Cu, Fe, Ni, Cd and Cr was observed in lime 2 treatment about 62.1%, 64.4%, 71.9%, 62.1% and 58.9% respectively; however higher reduction in BF of Zn and Pb was observed in lime 1 treatment during the composting process. Reducible and oxidizable fractions of Ni, Pb and Cd were not observed during the process. Addition of lime was very effective for reduction of bioavailability of heavy metals during composting of water hyacinth with cattle manure and sawdust.

关键词: composting     lime     heavy metals     bioavailability factor     speciation    

Iron oxidation-reduction and its impacts on cadmium bioavailability in paddy soils: a review

Chunhua ZHANG, Ying GE, Huan YAO, Xiao CHEN, Minkun HU

《环境科学与工程前沿(英文)》 2012年 第6卷 第4期   页码 509-517 doi: 10.1007/s11783-012-0394-y

摘要: Redox conditions in paddy soils may vary as they are submerged and drained during rice growth. This change may bring about reductive dissolution of iron (Fe) oxides and subsequent formation of secondary Fe-bearing minerals in rice paddies. The mobility and bioavailability of metal contaminants such as cadmium (Cd) in paddy soils are closely related to the chemical behaviors of Fe. Therefore, in this paper, advances in the study of paddy Fe redox transformations and their effects on Cd availability to rice are briefly reviewed. Current concepts presented in this review include the forms of Fe in paddy soils, the reactions involved in Fe oxidation-reduction, chemical factors affecting Fe redox processes, Cd availability to rice and the impacts of Fe transformation on Cd uptake and translocation in rice. Prospects for future research in this area are also discussed.

关键词: paddy soil     redox     iron     cadmium     bioavailability     rice    

Effects of rape straw and red mud on extractability and bioavailability of cadmium in a calcareous soil

Junxing YANG,Liqun WANG,Jumei LI,Dongpu WEI,Shibao CHEN,Qingjun GUO,Yibing MA

《环境科学与工程前沿(英文)》 2015年 第9卷 第3期   页码 419-428 doi: 10.1007/s11783-014-0674-9

摘要: Screening of cost-effective soil amendments is important to develop “ ” remediation techniques for cadmium (Cd) contaminated soils. In this study, different soil amendments, including red mud, a by-product of the alumina industry, and acid-treated, nano-treated by nano-particle milling, nano and acid-treated red muds, zeolite, corn straw, and rape straw, were evaluated to immobilize Cd in two added levels (2 and 5 mg Cd·kg soil) in a calcareous soil by single and sequential extractions and by cucumber ( L.) pot experiments. Results indicated that cruciferous rape straw significantly decreased the concentrations of water soluble, extractable Cd in soils, and Cd in cucumber plants, and it was more effective than gramineous corn straw. Also, red mud generally decreased the extractability and bioavailability of Cd added to calcareous soils more effectively than zeolite. Furthermore, the efficiency of red mud could be increased by the treatment of nano-particle milling due to the increase in specific surface area of red mud. It is potential to use rape straw and red mud as soil amendments to develop a cost-effective and efficient “ ” remediation technology for Cd mildly contaminated calcareous soils.

关键词: red mud     rape straw     cadmium     immobilization     calcareous soil    

Mitigation and remediation technologies for organic contaminated soils

Lizhong ZHU, Li LU, Dong ZHANG

《环境科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 373-386 doi: 10.1007/s11783-010-0253-7

摘要: Organic contaminated soils have become a widespread environmental problem, which may lead to a great threat to the quality of agricultural production and to human health. Physical, chemical, and biological technologies have been employed for the mitigation and remediation of organic contaminated soils. This paper reviews the progress of mitigation and remediation technologies for organic contaminated soils and suggests two different strategies for the mitigation of ‘slightly-contaminated’ agricultural soils and the remediation of ‘heavily-contaminated’ soils/sites, respectively. On this basis, directions for future research in this field are suggested.

关键词: organic contaminated soil     mitigation     remediation     bioavailability    

Biochars derived from carp residues: characteristics and copper immobilization performance in water environments

《环境科学与工程前沿(英文)》 2023年 第17卷 第6期 doi: 10.1007/s11783-023-1672-6

摘要:

● P-rich carp residues-derived biochars presented excellent Cu sorption capacity.

关键词: Biowaste     Pyrolytic temperature     Immobilization     Bioavailability     Remediation    

Exposure-response of Cr(III)-organic complexes to Saccharomyces cerevisiae

Nivedita CHATTERJEE, Zejiao LUO,

《环境科学与工程前沿(英文)》 2010年 第4卷 第2期   页码 196-202 doi: 10.1007/s11783-010-0008-5

摘要: Hexavalent chromium [Cr(VI)] bioreduction produces soluble Cr(III)-organic complexes. The Cr(III)-organic complexes are relatively stable once they are formed, and no data about their toxicity were reported. Therefore, this study aims to investigate the bioavailability and toxicity of the soluble Cr(III)-organic complexes. L-1 wild type yeast strain was chosen as the model organism and Cr(III)-citrate was selected as the representative compound of the Cr(III)-organic complexes. The short-term chronic aquatic toxicity tests of the Cr(III)-citrate was explored by measuring growth inhibition, direct viable cell count, dry biomass, biosorption, and the amount of CO production. Cr(III)-citrate exerted a toxicity of 51mg/L with an , which was calculated from the percent growth inhibition. These toxicity data would be helpful to define the toxic potential of the organo-chromium-III compounds in the environment.

关键词: Cr(III)-organic complexes     Saccharomyces cerevisiae     toxicity     EC50     bioavailability    

载有穿心莲内酯的微乳液和纳米乳液制剂——改善“苦味之王” 的生物利用度、靶组织分布及功效 Review

Marta Casamonti, Laura Risaliti, Giulia Vanti, Veri Piazzini, Maria Camilla Bergonzi, Anna Rita Bilia

《工程(英文)》 2019年 第5卷 第1期   页码 69-75 doi: 10.1016/j.eng.2018.12.004

摘要:

穿心莲内酯(AG)为爵床科植物穿心莲(Andrographis paniculata)的特征性成分。该植物为亚洲著名药用植物,在印度、中国和泰国得到广泛使用。《中华人民共和国药典》(简称《中国药典》)收载了中药穿心莲的药材标准,记载这种草药的煎剂可“清热、解毒、消肿”。穿心莲具有众多潜在活性,从抗炎到抗糖尿病作用,从神经保护到抗肿瘤活性,从保肝到抗肥胖特性。然而,AG的生物利用度较低、水溶性较差,因此限制了给药后在体内的分布和积累。此外,AG在胃肠道碱性和酸性环境中不稳定,据报道其半衰期极为短暂。在为提高AG的水溶性和渗透性而采取的各种策略中,技术途径是开发适合的给药系统最有用的方法。本文综述了与载有AG的微粒(MP)和纳米颗粒(NP)相关的已有研究工作。目前已开发出基于聚乳酸- 羟基乙酸(PLGA)、海藻酸和葡聚糖衍生物的微粒,分别用于肠胃外口服和肺部给药。NP包括囊泡(脂质体和类脂质体)、聚合NP(基于聚乙烯醇、聚合苯基硼酸、PLGA、人血清白蛋白、聚氰基丙烯酸乙酯和聚合物胶束)、固体脂质NP、微乳液(ME)和纳米乳液(NE)、黄金NP、纳米晶体和纳米混悬液。据报道,所述载有AG的给药系统的生物利用度、靶组织分布和功效都得到了优化。

关键词: 穿心莲     爵床科     穿心莲内酯     给药系统     微粒子和纳米颗粒     提高生物利用度     靶组织分布    

Role of the forkhead transcription factor FOXO-FOXM1 axis in cancer and drug resistance

null

《医学前沿(英文)》 2012年 第6卷 第4期   页码 376-380 doi: 10.1007/s11684-012-0228-0

摘要:

The forkhead transcription factors FOXO and FOXM1 have pivotal roles in tumorigenesis and in mediating chemotherapy sensitivity and resistance. Recent research shows that the forkhead transcription factor FOXM1 is a direct transcriptional target repressed by the forkhead protein FOXO3a, a vital downstream effector of the PI3K-AKT-FOXO signaling pathway. Intriguingly, FOXM1 and FOXO3a also compete for binding to the same gene targets, which have a role in chemotherapeutic drug action and sensitivity. An understanding of the role and regulation of the FOXO-FOXM1 axis will impact directly on our knowledge of chemotherapeutic drug action and resistance in patients, and provide new insights into the design of novel therapeutic strategy and reliable biomarkers for prediction of drug sensitivity.

关键词: FOXO3a     FOXM1     transcription factor     cancer     drug resistance     tumorigenesis    

LSSVM-based approach for refining soil failure criteria and calculating safety factor of slopes

Shiguo XIAO; Shaohong LI

《结构与土木工程前沿(英文)》 2022年 第16卷 第7期   页码 871-881 doi: 10.1007/s11709-022-0863-8

摘要: The failure criteria of practical soil mass are very complex, and have significant influence on the safety factor of slope stability. The Coulomb strength criterion and the power-law failure criterion are classically simplified. Each one has limited applicability owing to the noticeable difference between calculated predictions and actual results in some cases. In the work reported here, an analysis method based on the least square support vector machine (LSSVM), a machine learning model, is purposefully provided to establish a complex nonlinear failure criterion via iteration computation based on strength test data of the soil, which is of more extensive applicability to many problems of slope stability. In particular, three evaluation indexes including coefficient of determination, mean absolute percentage error, and mean square error indicate that fitting precision of the machine learning-based failure criterion is better than those of the linear Coulomb criterion and nonlinear power-law criterion. Based on the proposed LSSVM approach to determine the failure criterion, the limit equilibrium method can be used to calculate the safety factor of three-dimensional slope stability. Analysis of results of the safety factor of two three-dimensional homogeneous slopes shows that the maximum relative errors between the proposed approach and the linear failure criterion-based method and the power-law failure criterion-based method are about 12% and 7%, respectively.

关键词: slope stability     safety factor     failure criterion     least square support vector machine    

lncR-GAS5 upregulates the splicing factor to impair endothelial autophagy, leading to atherogenesis

《医学前沿(英文)》 2023年 第17卷 第2期   页码 317-329 doi: 10.1007/s11684-022-0931-4

摘要: Long noncoding RNAs (lncRNAs) play a critical role in the regulation of atherosclerosis. Here, we investigated the role of the lncRNA growth arrest-specific 5 (lncR-GAS5) in atherogenesis. We found that the enforced expression of lncR-GAS5 contributed to the development of atherosclerosis, which presented as increased plaque size and reduced collagen content. Moreover, impaired autophagy was observed, as shown by a decreased LC3II/LC3I protein ratio and an elevated P62 level in lncR-GAS5-overexpressing human aortic endothelial cells. By contrast, lncR-GAS5 knockdown promoted autophagy. Moreover, serine/arginine-rich splicing factor 10 (SRSF10) knockdown increased the LC3II/LC3I ratio and decreased the P62 level, thus enhancing the formation of autophagic vacuoles, autolysosomes, and autophagosomes. Mechanistically, lncR-GAS5 regulated the downstream splicing factor SRSF10 to impair autophagy in the endothelium, which was reversed by the knockdown of SRSF10. Further results revealed that overexpression of the lncR-GAS5-targeted gene miR-193-5p promoted autophagy and autophagic vacuole accumulation by repressing its direct target gene, SRSF10. Notably, miR-193-5p overexpression decreased plaque size and increased collagen content. Altogether, these findings demonstrate that lncR-GAS5 partially contributes to atherogenesis and plaque instability by impairing endothelial autophagy. In conclusion, lncR-GAS5 overexpression arrested endothelial autophagy through the miR-193-5p/SRSF10 signaling pathway. Thus, miR-193-5p/SRSF10 may serve as a novel treatment target for atherosclerosis.

关键词: lncR-GAS5     miR-193-5p     splicing factor SRSF10     autophagy     atherogenesis    

The calculation of equivalence factor for ecological footprints in China: a methodological note

Moucheng LIU,Wenhua LI,Dan ZAHNG,Ning SU

《环境科学与工程前沿(英文)》 2015年 第9卷 第6期   页码 1015-1024 doi: 10.1007/s11783-014-0670-0

摘要: The Ecological Footprint (EF), a physical indicator to measure the extent of humanity’s use of natural resources, has gained much attention since it was first used by Wackernagel and Rees in 1996. In order to appraise land area types with different levels of productivity, they introduced the concept of an equivalence factor. This relates to the average primary biomass productivities of different types of land (i.e. arable land, pasture, forest, water/fishery, built-up land and fossil energy land) to the regional average primary biomass productivity of all land types in a given year. Hence, the equivalence factor is an important parameter in the EF model and it directly affects the reliability of all results. Thus, this article calculates equivalence factors on the national and provincial levels in China based on Net Primary Production (NPP) from MODIS 1 km data in 2008. Firstly, based on the Light Utility Efficiency and CASA model, the NPP of different biologically productive lands of China and of different provinces was calculated. Secondly, China’s equivalence factor for 6 land area types was calculated based on NPP: arable land and built-up land has an equivalence factor of 1.71, forest and fossil energy land has a factor of 1.41, pasture has a factor of 0.44 and water/fishery 0.35; Finally, the equivalence factor of 6 land area types in different provinces was also calculated. The NPP of each ecosystem type varies along with the equivalence factor in different provinces. However, the ranking of the equivalence factors in different provinces remain the same, with that of arable land being the largest, and the water/fishery being the smallest.

关键词: ecological footprint     equivalence factor     net primary production     biological capacity     land types    

A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

《结构与土木工程前沿(英文)》 2021年 第15卷 第4期   页码 877-894 doi: 10.1007/s11709-021-0756-2

摘要: Many bridge design specifications consider multi-lane factors (MLFs) a critical component of the traffic load model. Measured multi-lane traffic data generally exhibit significant lane disparities in traffic loads over multiple lanes. However, these disparities are not considered in current specifications. To address this drawback, a multi-coefficient MLF model was developed based on an improved probabilistic statistical approach that considers the presence of multiple trucks. The proposed MLF model and approach were calibrated and demonstrated through an example site. The model sensitivity analysis demonstrated the significant influence of lane disparity of truck traffic volume and truck weight distribution on the MLF. Using the proposed approach, the experimental site study yielded MLFs comparable with those directly calculated using traffic load effects. The exclusion of overloaded trucks caused the proposed approach, existing design specifications, and conventional approach of ignoring lane load disparity to generate comparable MLFs, while the MLFs based on the proposed approach were the most comprehensive. The inclusion of overloaded trucks caused the conventional approach and design specifications to overestimate the MLFs significantly. Finally, the benefits of the research results to bridge practitioners were discussed.

关键词: bridges     multi-lane factor     traffic load     lane load disparity     multi-truck presence     weigh-in-motion data    

Numerical investigation of the influence of kinetics and shape factor on barium sulfate precipitation

Zheng WANG, Zai-Sha MAO, Chao YANG, Qinghua ZHANG, Jingcai CHENG

《化学科学与工程前沿(英文)》 2009年 第3卷 第3期   页码 272-281 doi: 10.1007/s11705-009-0023-x

摘要: The effect of kinetics and shape factor on barium sulfate precipitation in a continuous stirred tank has been investigated numerically through solving the standard momentum and mass transport equations in combination with the moment equations for crystal population balance. The numerical method was validated with the literature data. The simulated results include the distribution of the local supersaturation ratio in the reactor, the mean crystal size, and the coefficient of variation. The simulation results show that the value of shape factor used in the model affected greatly the mean crystal size and the moments of the crystal size distribution. The influence of the kinetic expressions on the simulation is also analyzed. It is important to investigate the relationship of the shape factor with the precipitator type and other operation conditions to obtain reliable simulation results and suitable kinetic equations of crystal nucleation and growth rates.

关键词: stirred tank     numerical simulation     precipitation     shape factor     crystal kinetics    

Performance and mechanism for cadmium and lead adsorption from water and soil by corn straw biochar

Tong Chi,Jiane Zuo,Fenglin Liu

《环境科学与工程前沿(英文)》 2017年 第11卷 第2期 doi: 10.1007/s11783-017-0921-y

摘要: Corn straw biochar prepared under 400 °C was the best Cd and Pb adsorption capacity Maximum adsorption capacity of Cd and Pb were 43.48 and 22.73 mg·g , respectively The dominant mechanism of Cd and Pb adsorption was precipitation Biochar could reduce the bioavailability of heavy metals when mixed with soil Cadmium (Cd) and lead (Pb) in water and soil could be adsorbed by biochar produced from corn straw. Biochar pyrolyzed under 400°C for 2 h could reach the ideal removal efficiencies (99.24% and 98.62% for Cd and Pb, respectively) from water with the biochar dosage of 20 g·L and initial concentration of 20 mg·L . The pH value of 4–7 was the optimal range for adsorption reaction. The adsorption mechanism was discussed on the basis of a range of characterizations, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and Raman analysis; it was concluded as surface complexation with active sorption sites (-OH, -COO-), coordination with π electrons (C= C, C= O) and precipitation with inorganic anions (OH , CO , SO ) for both Cd and Pb. The sorption isotherms fit Langmuir model rather than Freundlich model, and the saturated sorption capacities for Cd and Pb were 38.91 mg·g and 28.99 mg·g , respectively. When mixed with soil, biochar could effectively increase alkalinity and reduce bioavailability of heavy metals. Thus, biochar derived from corn straw would be a green material for both removal of heavy metals and amelioration of soil.

关键词: Corn straw     Biochar     Heavy metals     Sorption isotherm     Bioavailability    

Nanocrystal technology for drug formulation and delivery

Tzu-Lan CHANG, Honglei ZHAN, Danni LIANG, Jun F. LIANG

《化学科学与工程前沿(英文)》 2015年 第9卷 第1期   页码 1-14 doi: 10.1007/s11705-015-1509-3

摘要: With the development of modern technology like high throughput screening, combinatorial chemistry and computer aid drug design, the drug discovery process has been dramatically accelerated. However, new drug candidates often exhibit poor aqueous or even organic medium solubility. Additionally, many of them may have low dissolution velocity and low oral bioavailability. Nanocrystal formulation sheds new light on advanced drug development. Due to small (nano- or micro- meters) sizes, the increased surface-volume ratio leads to dramatically enhanced drug dissolution velocity and saturation solubility. The simplicity in preparation and the potential for various administration routes allow drug nanocrystals to be a novel drug delivery system for specific diseases (i.e. cancer). In addition to the comprehensive review of different technologies and methods in drug nanocrystal preparation, suspension, and stabilization, we will also compare nano- and micro-sized drug crystals in pharmaceutical applications and discuss current nanocrystal drugs on the market and their limitations.

关键词: drug nanocrystal     nanotechnology     formulation     bioavailability     stabilizers     drug delivery    

标题 作者 时间 类型 操作

Effect of lime on speciation of heavy metals during composting of water hyacinth

Jiwan SINGH,Ajay S. KALAMDHAD

期刊论文

Iron oxidation-reduction and its impacts on cadmium bioavailability in paddy soils: a review

Chunhua ZHANG, Ying GE, Huan YAO, Xiao CHEN, Minkun HU

期刊论文

Effects of rape straw and red mud on extractability and bioavailability of cadmium in a calcareous soil

Junxing YANG,Liqun WANG,Jumei LI,Dongpu WEI,Shibao CHEN,Qingjun GUO,Yibing MA

期刊论文

Mitigation and remediation technologies for organic contaminated soils

Lizhong ZHU, Li LU, Dong ZHANG

期刊论文

Biochars derived from carp residues: characteristics and copper immobilization performance in water environments

期刊论文

Exposure-response of Cr(III)-organic complexes to Saccharomyces cerevisiae

Nivedita CHATTERJEE, Zejiao LUO,

期刊论文

载有穿心莲内酯的微乳液和纳米乳液制剂——改善“苦味之王” 的生物利用度、靶组织分布及功效

Marta Casamonti, Laura Risaliti, Giulia Vanti, Veri Piazzini, Maria Camilla Bergonzi, Anna Rita Bilia

期刊论文

Role of the forkhead transcription factor FOXO-FOXM1 axis in cancer and drug resistance

null

期刊论文

LSSVM-based approach for refining soil failure criteria and calculating safety factor of slopes

Shiguo XIAO; Shaohong LI

期刊论文

lncR-GAS5 upregulates the splicing factor to impair endothelial autophagy, leading to atherogenesis

期刊论文

The calculation of equivalence factor for ecological footprints in China: a methodological note

Moucheng LIU,Wenhua LI,Dan ZAHNG,Ning SU

期刊论文

A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

期刊论文

Numerical investigation of the influence of kinetics and shape factor on barium sulfate precipitation

Zheng WANG, Zai-Sha MAO, Chao YANG, Qinghua ZHANG, Jingcai CHENG

期刊论文

Performance and mechanism for cadmium and lead adsorption from water and soil by corn straw biochar

Tong Chi,Jiane Zuo,Fenglin Liu

期刊论文

Nanocrystal technology for drug formulation and delivery

Tzu-Lan CHANG, Honglei ZHAN, Danni LIANG, Jun F. LIANG

期刊论文