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排序方式: 共有8562条查询结果,搜索用时 15 毫秒
1.
Krzysztof M. Tokarz Wojciech Wesoowski Barbara Tokarz Wojciech Makowski Anna Wysocka Roman J. Jdrzejczyk Karolina Chrabaszcz Kamilla Malek Anna Kostecka-Gugaa 《International journal of molecular sciences》2021,22(2)
Grass pea (Lathyrus sativus) is a leguminous plant of outstanding tolerance to abiotic stress. The aim of the presented study was to describe the mechanism of grass pea (Lathyrus sativus L.) photosynthetic apparatus acclimatisation strategies to salinity stress. The seedlings were cultivated in a hydroponic system in media containing various concentrations of NaCl (0, 50, and 100 mM), imitating none, moderate, and severe salinity, respectively, for three weeks. In order to characterise the function and structure of the photosynthetic apparatus, Chl a fluorescence, gas exchange measurements, proteome analysis, and Fourier-transform infrared spectroscopy (FT-IR) analysis were done inter alia. Significant differences in the response of the leaf and stem photosynthetic apparatus to severe salt stress were observed. Leaves became the place of harmful ion (Na+) accumulation, and the efficiency of their carboxylation decreased sharply. In turn, in stems, the reconstruction of the photosynthetic apparatus (antenna and photosystem complexes) activated alternative electron transport pathways, leading to effective ATP synthesis, which is required for the efficient translocation of Na+ to leaves. These changes enabled efficient stem carboxylation and made them the main source of assimilates. The observed changes indicate the high plasticity of grass pea photosynthetic apparatus, providing an effective mechanism of tolerance to salinity stress. 相似文献
2.
This study proposes a multiperiod mixed integer linear programming model for the management of a single municipal solid waste (MSW) treatment plant with sustainability as the objective. Discrete and continuous variables define the capacity selections for diverse MSW technologies, and the operation of the MSW network, respectively. The economic target is considered to maximize the net present value. The environmental impact is the minimization of a normalized environmental objective function (NEOF). The social target is the maximization of jobs. An interesting feature about the research work is the requirement of biodrying technologies for MSW moisture content control. Due to the conflicted nature among the sustainability components, a multiobjective optimization (MO) is carried out to find the Pareto optimal solutions. The MO results show that the Pareto optimal solutions vary around profit range of $4.9–8.5 billion, NEOF impact range of 3.2–3.6 units, and social benefit range of 2700–4828 jobs. 相似文献
3.
Ashish Ganvir Mohit Gupta Nitish Kumar Nicolaie Markocsan 《Ceramics International》2021,47(1):272-283
This paper investigates the influence of suspension characteristics on microstructure and performance of suspensions plasma sprayed (SPS) thermal barrier coatings (TBCs). Five suspensions were produced using various suspension characteristics, namely, type of solvent and solid load content, and the resultant suspensions were utilized to deposit five different TBCs under identical processing conditions. The produced TBCs were evaluated for their performance i.e. thermal conductivity, thermal cyclic fatigue (TCF) and thermal shock (TS) lifetime. This experimental study revealed that the differences in the microstructure of SPS TBCs produced using varied suspensions resulted in a wide-ranging overall TBC performance. All TBCs exhibited thermal conductivity lower than 1 W/(m. K) except water-ethanol mixed suspension produced TBC. The TS lifetime was also affected to a large extent where 10 wt % solid loaded ethanol and 25 wt % solid loaded water suspensions produced TBCs exhibited the highest and the lowest lifetime, respectively. On the contrary, TCF lifetime was not as significantly affected as thermal conductivity and TS lifetime, and all ethanol suspensions showed marginally better TCF lifetime than water and ethanol-water mixed suspensions deposited TBCs. 相似文献
4.
《International Journal of Hydrogen Energy》2022,47(6):4222-4235
Quantitative Risk Assessment (QRA) supports the development of risk-informed safety codes and standards which are employed to enable the safe deployment of hydrogen technologies essential to decarbonize the transportation sector. System reliability data is a necessary input for rigorous QRA. The lack of reliability data for bulk liquid hydrogen (LH2) storage systems located on site at fueling stations limits the use of QRAs. In turn, this hinders the ability to develop the necessary safety codes and standards that enable worldwide deployment of these stations. Through a QRA-based analysis of a LH2 storage system, this work focuses on identifying relevant scenario and probability data currently available and ascertaining future data collection requirements regarding risks specific to liquid hydrogen releases. The work developed consists of the analysis of a general bulk LH2 storage system design located at a hydrogen fueling station. Failure Mode and Effect Analysis (FMEA) and traditional QRA modeling tools such as Event Sequence Diagrams (ESD) and Fault Tree Analysis (FTA) are employed to identify, rank, and model risk scenarios related to the release of LH2. Based on this analysis, scenario and reliability data needs to add LH2-related components to QRA are identified with the purpose of improving the future safety and risk assessment of these systems. 相似文献
5.
针对金融领域中智能客服的句子相似度计算方法进行了研究。利用基于词性的分词纠正模型减少中文歧义词、金融相关词汇的分词错误;通过词向量方法和循环神经网络分别提取词语级和句子级的语义特征,并且得到句子向量;用融合层计算出句子向量间的差异特征;对差异特征进行降维和归一化得到句子相似度计算结果。实验结果表明,该方法具有较高的准确率和[F1]值。 相似文献
6.
Influence analysis of bracket set on seismic performance of steel eave columns in Chinese traditional style buildings 下载免费PDF全文
Jianyang Xue Linlin Ma Zhanjing Wu Weixin Gao 《The Structural Design of Tall and Special Buildings》2018,27(8)
This paper presents influence analysis of bracket set on seismic performance of steel eave columns in Chinese traditional style buildings. Eight 1/1.5‐scale steel eave columns were constructed and tested under low cyclic reversed loading, including 4 specimens with bracket set and 4 specimens without bracket set. Based on the analysis of the strain of the specimens, the failure modes of the specimens were obtained. In addition, the hysteresis loops, skeleton curves, degradations of stiffness and strength, ductility, and dissipation capacities of the specimens were analyzed. Bracket set changed the force transfer mechanisms and failure modes of the specimens and had a significant influence on the seismic performance of the specimens. Compared with the specimens without bracket set, the yielded and ultimate bearing capacities of the specimens with bracket set improved by 30.7% and 24.0%, respectively. And also, the stiffness of the specimens with bracket set at the yielded and ultimate points increased by 52.8% and 135.6%. The dissipation capacities of the specimens with bracket set were 2.12 times those of the specimens without bracket set at yielded load. However, the ductility of the specimens with bracket set slightly decreased by 8.5%. It was shown that the seismic performance of the specimens with bracket set was better than that of the specimens without bracket set. The work in this paper provides a basis for further theoretical study on the seismic performance of steel eave columns in Chinese traditional style buildings. 相似文献
7.
Francesco Caruso Manrose Singh Stuart Belli Molly Berinato Miriam Rossi 《International journal of molecular sciences》2020,21(23)
We describe the potential anti coronavirus disease 2019 (COVID-19) action of the methide quinone inhibitor, celastrol. The related methide quinone dexamethasone is, so far, among COVID-19 medications perhaps the most effective drug for patients with severe symptoms. We observe a parallel redox biology behavior between the antioxidant action of celastrol when scavenging the superoxide radical, and the adduct formation of celastrol with the main COVID-19 protease. The related molecular mechanism is envisioned using molecular mechanics and dynamics calculations. It proposes a covalent bond between the S(Cys145) amino acid thiolate and the celastrol A ring, assisted by proton transfers by His164 and His41 amino acids, and a π interaction from Met49 to the celastrol B ring. Specifically, celastrol possesses two moieties that are able to independently scavenge the superoxide radical: the carboxylic framework located at ring E, and the methide-quinone ring A. The latter captures the superoxide electron, releasing molecular oxygen, and is the feature of interest that correlates with the mechanism of COVID-19 inhibition. This unusual scavenging of the superoxide radical is described using density functional theory (DFT) methods, and is supported experimentally by cyclic voltammetry and X-ray diffraction. 相似文献
8.
9.
多酚氧化形成的醌类物质作为强亲电体可能与食品体系中多种亲核物质作用,进而引发系列营养与安全问题。利用电化学工作站研究了酸性(pH 5.0)、中性(pH 7.0)和碱性(pH 8.0)条件下槲皮素醌与5种氨基化合物、2种巯基化合物以及牛血清白蛋白(BSA)的相互作用。结果表明:槲皮素醌在pH 7.0或pH 8.0条件下与8种亲核物质的互作效率显著高于pH 5.0;相同作用条件下,槲皮素醌与巯基化合物互作效率显著优于氨基化合物;在pH 7.0、扫描速率10 mV/s的条件下,槲皮素醌(0.08 mmol/L,以槲皮素计)与5种氨基化合物(16.0 mmol/L)互作效率排序为:L-赖氨酸(55.13%±5.37%)>L-精氨酸(39.58%±4.64%)>L-甲硫氨酸(17.80%±2.72%)>甘氨酸(~0.00%)≈Nα-乙酰-L-赖氨酸(~0.00%),槲皮素醌(0.08 mmol/L,以槲皮素计)与2种巯基化合物及BSA(0.048 mmol/L)互作效率排序为:L-半胱氨酸(63.17%±1.51%)>Nα-乙酰-L-半胱氨酸(54.28%±2.60%)>BSA(37.55%±5.98%)。研究表明:槲皮素氧化形成的醌类物质可以化学改性蛋白质,消耗体系必需氨基酸。 相似文献
10.