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91.
煤电在中国电力供应结构中占据主导地位,其环境影响是研究热点之一。建立中国煤电生命周期二氧化碳和大气污染物排放分析模型,基于文献调研构建参数数据库,测算中国煤电的单位发电量排放。结果表明,近年来中国煤电生命周期单位发电量的CO2、SO2、NOx和PM2.5排放分别为838.6 g/(kW·h)、0.34 g/(kW·h)、0.32 g/(kW·h)和0.08 g/(kW·h)。其中煤电单位发电量大气污染物排放,比实施超低排放改造前,下降幅度超过90%。研究发现,增大单机机组规模和进行超低排放改造能够有效降低煤电发电过程的大气污染物排放,采用煤电燃烧后碳捕集和存储(carbon capture and storage, CCS)处理技术能够使煤电CO2排放下降到144 g/(kW·h),助力碳中和目标实现。如果不采用更加严格的大气污染物排放标准和处理方式,CCS技术可能会使煤电大气污染物排放强度上升30%~40%,这与碳捕集过程使用的技术有关。  相似文献   
92.
Interleukin (IL)-33 is a member of the interleukin (IL)-1 family of cytokines linked to the development of inflammatory conditions and cancer in the gastrointestinal tract. This study is designed to investigate whether IL-33 has a direct effect on human gastric epithelial cells (GES-1), the human gastric adenocarcinoma cell line (AGS), and the gastric carcinoma cell line (NCI-N87) by assessing its role in the regulation of cell proliferation, migration, cell cycle, and apoptosis. Cell cycle regulation was also determined in ex vivo gastric cancer samples obtained during endoscopy and surgical procedures. Cell lines and tissue samples underwent stimulation with rhIL-33. Proliferation was assessed by XTT and CFSE assays, migration by wound healing assay, and apoptosis by caspase 3/7 activity assay and annexin V assay. Cell cycle was analyzed by means of propidium iodine assay, and gene expression regulation was assessed by RT-PCR profiling. We found that IL-33 has an antiproliferative and proapoptotic effect on cancer cell lines, and it can stimulate proliferation and reduce apoptosis in normal epithelial cell lines. These effects were also confirmed by the analysis of cell cycle gene expression, which showed a reduced expression of pro-proliferative genes in cancer cells, particularly in genes involved in G0/G1 and G2/M checkpoints. These results were confirmed by gene expression analysis on bioptic and surgical specimens. The aforementioned results indicate that IL-33 may be involved in cell proliferation in an environment- and cell-type-dependent manner.  相似文献   
93.
Simulated microgravity (SMG) induced the changes in cell proliferation and cytoskeleton organization, which plays an important factor in various cellular processes. The inhibition in cell cycle progression has been considered to be one of the main causes of proliferation inhibition in cells under SMG, but their mechanisms are still not fully understood. This study aimed to evaluate the effects of SMG on the proliferative ability and cytoskeleton changes of Chang Liver Cells (CCL-13). CCL-13 cells were induced SMG by 3D clinostat for 72 h, while the control group were treated in normal gravity at the same time. The results showed that SMG reduced CCL-13 cell proliferation by an increase in the number of CCL-13 cells in G0/G1 phase. This cell cycle phase arrest of CCL-13 cells was due to a downregulation of cell cycle-related proteins, such as cyclin A1 and A2, cyclin D1, and cyclin-dependent kinase 6 (Cdk6). SMG-exposed CCL-13 cells also exhibited a downregulation of α-tubulin 3 and β-actin which induced the cytoskeleton reorganization. These results suggested that the inhibited proliferation of SMG-exposed CCL-13 cells could be associate with the attenuation of major cell cycle regulators and main cytoskeletal proteins.  相似文献   
94.
Cell division cycle 25A (Cdc25A) is a dual-specificity phosphatase that is overexpressed in several cancer cells and promotes tumorigenesis. In normal cells, Cdc25A expression is regulated tightly, but the changes in expression patterns in cancer cells that lead to tumorigenesis are unknown. In this study, we showed that ubiquitin-specific protease 29 (USP29) stabilized Cdc25A protein expression in cancer cell lines by protecting it from ubiquitin-mediated proteasomal degradation. The presence of USP29 effectively blocked polyubiquitination of Cdc25A and extended its half-life. CRISPR-Cas9-mediated knockdown of USP29 in HeLa cells resulted in cell cycle arrest at the G0/G1 phase. We also showed that USP29 knockdown hampered Cdc25A-mediated cell proliferation, migration, and invasion of cancer cells in vitro. Moreover, NSG nude mice transplanted with USP29-depleted cells significantly reduced the size of the tumors, whereas the reconstitution of Cdc25A in USP29-depleted cells significantly increased the tumor size. Altogether, our results implied that USP29 promoted cell cycle progression and oncogenic transformation by regulating protein turnover of Cdc25A.  相似文献   
95.
In recent years, highly efficient oil/water separation materials have brought much attention. It requests superhydrophobic surfaces with a rapid and facile separation process, excellent durability, and large-scale fabrication. Herein, a facile vapor-liquid sol-gel, and free radical polymerization reaction method to prepare the durable and robust superhydrophobic cotton fabric is proposed. Moreover, the fabric can be used for highly efficient and various oil/water separation. It is prepared via a simple two-step process, including a vapor-liquid sol-gel process to deposit with thiols particles, and then followed a free radical polymerization reaction to graft 2,2,3,4,4,4-hexafluorobutyl methacrylate. Scanning electron microscopy and Fourier transform infrared spectrometry prove that the rough structures are generated from the hydrolysis condensation reaction between tetraethyl orthosilicate and 3-mercaptopropyltriethoxysilane. As a result, the synthetic chemical composition provided by the natural fabric and silica nanoparticles synergistically construct a superhydrophobic surface with water contact angles and shedding angle of 158° and 9°, respectively. Additionally, the treated fabric exhibits excellent chemical resistance and self-cleaning ability. Remarkably, the fabric still retains superhydrophobic and excellent mechanical robustness after 30 cycles of various oil/water separation. In summary, the resultant fabrics with excellent chemical resistance, remarkable mechanical robustness, and versatile separation abilities have potential applications in various oil/water separations.  相似文献   
96.
太阳能发电技术中传热性能的优劣影响着太阳能的利用程度。选用石墨作为强化相变材料传热性能的添加剂与三元混合熔盐(K2CO3-NaCl-Li2CO3)按照石墨质量分数为5%、10%、15%进行混合制备,使用TC3000通用型导热系数测试仪测定16种试样的导热系数。并测试经历300次循环储能、释能实验试样的导热系数循环稳定性。实验结果表明:添加石墨后的混合相变材料导热系数最高可提升至原混合材料的3.38倍,当石墨的质量分数为15%时,混合相变材料的导热系数最大。在经历300次储能、释能实验后,材料的导热系数基本保持稳定,变化浮动不高于15%。石墨作为强化材料的添加剂,可有效提升强化材料的传热性能,具有实际工程的应用价值。  相似文献   
97.
孙晓辉  檀雷 《水泥工程》2021,34(5):52-54
以某一新型二代水泥技术的7 000 t/d熟料生产线为例,单纯的采用汽水朗肯循环,存在热量回收不彻底,部分低品位余热资源无法有效回收等问题。采用汽水朗肯循环及有机朗肯循环联合发电系统的方案,结果表明:联合朗肯循环系统发电功率提高了614 kW,吨熟料发电量增加了2.1 kWh/kg,提高了8%;净发电功率提高了511 kW,净发电量实际提高了7.1%,提高了水泥余热回收的效率。  相似文献   
98.
周强  刘伟  徐晓刚 《机床与液压》2004,68(5):182-184
在大型复杂设计活动中,由于缺少系统化的交流机制来保障设计过程中设计信息的及时、准确地传递,产生设计冲突,进而导致整个设计在时间上的拖延。本文以此为出发点,提出了解决上述冲突的基于DSM与QFD技术的集成设计联合矩阵及其决策流程;支持企业缩短其新产品开发的周期。  相似文献   
99.
研究了快淬工艺对无钴AB5型LaxMm1-x(NiMnSiAlFe)4.9(x=0,0.45,0.75,1.0)合金微观结构及电化学循环稳定性的影响.结果表明快淬处理显著改善合金的成分均匀性,使晶粒细化,并显著提高合金的循环稳定性.当淬速从0m/s增加到28 m/s时,经300次充放循环后,x=0.45合金的容量衰减率D从0.28 mAh/g·c-1(c代表一次循环)下降到0.13mAh/g·c-1;x=1.0合金的容量衰减率D从0.3mAh/g·c-1下降到0.14mAh/g·c-1.  相似文献   
100.
Fe替代Co对AB5型贮氢合金循环稳定性的影响   总被引:2,自引:0,他引:2  
用铸造及快淬的方法制备了稀土基AB5型Mm(NiMnSiAl)4.3Co0.6-xFex(x=0,0.1,0.2,0.3,0.4,0.5,0.6)贮氢合金,用XRD。TEM及SEM观测了铸态及快淬态的微观结构,测试了合金在铸态及快淬态下的电化学循环稳定性。研究了Fe替代Co对铸态及快淬态贮氢合金微观结构及循环稳定性的影响。研究结果表明,Fe替代Co对铸态及快淬态合金的相结构没有明显影响,但对合金的循环稳定性产生显著影响。Fe替代Co能不同程度地改善铸态及快淬态合金的循环稳定性,但对快淬态合金循环寿命的改善更加显著,导致这一结果的主要原因是Fe替代Co使快淬态合金的微观组织显著细化。  相似文献   
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