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171.
煤焦膨胀特性与残灰颗粒物的形成 总被引:3,自引:0,他引:3
研究了煤焦的膨胀特性及其对1~5μm残灰颗粒物生成的影响.将一种烟煤筛分为小于63μm,[63~100)μm和[100~200)μm三种粒径,并在实验室沉降炉中进行了热解和燃烧实验,反应温度分别为1 373 K,1 523 K和1 673 K.利用激光粒度分析仪和扫描电子显微镜等对热解和燃烧产物进行了分析.研究结果表明,该种烟煤由于含有较高的镜质组成分,在热解过程中表现出明显的膨胀特性,而且煤粉粒径越小,其镜质组含量越高,因此在热解过程中膨胀越厉害,形成的煤胞型颗粒越多.膨胀厉害的煤焦在燃烧过程中很容易发生破碎,形成更多的1~5μm残灰颗粒物. 相似文献
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173.
Journal of Systems Science and Complexity - This paper addresses the distributed adaptive optimization problem over second-order multi-agent networks (MANs) with nonuniform gradient gains. A... 相似文献
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175.
Aiming at on-line controlling of Direct Methanol Fuel Cell (DMFC) stack, an adaptive neural fuzzy inference technology is adopted in the modeling and control of DMFC temperature system. In the modeling process, an Adaptive Neural Fuzzy Inference System (ANFIS) identification model of DMFC stack temperature is developed based on the input-output sampled data, which can avoid the internal complexity of DMFC stack. In the controlling process, with the network model trained well as the reference model of the DMFC control system, a novel fuzzy genetic algorithm is used to regulate the parameters and fuzzy rules of a neural fuzzy controller. In the simulation, compared with the nonlinear Proportional Integral Derivative (PID) and traditional fuzzy algorithm, the improved neural fuzzy controller designed in this paper gets better performance, as demonstrated by the simulation results. 相似文献
176.
177.
Kai Zhao Xingyu Zhao Yaping Tu Qi Miao Dongxu Cao Wenjuan Duan Yang Sun Jincheng Wang Taotao Wei Fuyu Yang 《Cellular and molecular life sciences : CMLS》2010,67(15):2665-2678
We have reported that chymotrypsin B (CtrB) is not just a digestive enzyme but is also stored in lysosomes. Herein, we demonstrated a broad distribution of CtrB and explored the involvement of CtrB in apoptosis. Exposure of RH-35 cells to H2O2 or palmitate induced the redistribution of lysosomal CtrB into the cytoplasm as a result of lysosomal membrane permeabilization (LMP). Suppression of CtrB significantly blocked apoptosis, while overexpression of CtrB sensitized apoptosis markedly. CtrB could cleave Bid under neutral conditions. In RH-35 cells with Bid silenced, apoptosis induced by CtrB protein was attenuated, suggesting that CtrB mediates apoptosis of RH-35 cells mainly through processing Bid. Our data also suggest that LMP occurs earlier than mitochondrial outer membrane permeabilization; Bid activation initiated by caspase-8 might be reinforced by CtrB in consequence of LMP, which causes a positive feedback loop leading to the accumulation of tBid, and results in lysosome- and mitochondrion-dependent apoptosis. 相似文献
178.
Lin Z Bei JX Shen M Li Q Liao Z Zhang Y Lv Q Wei Q Low HQ Guo YM Cao S Yang M Hu Z Xu M Wang X Wei Y Li L Li C Li T Huang J Pan Y Jin O Wu Y Wu J Guo Z He P Hu S Wu H Song H Zhan F Liu S Gao G Liu Z Li Y Xiao C Li J Ye Z He W Liu D Shen L Huang A Wu H Tao Y Pan X Yu B Tai ES Zeng YX Ren EC Shen Y Liu J Gu J 《Nature genetics》2012,44(1):73-77
To identify susceptibility loci for ankylosing spondylitis, we performed a two-stage genome-wide association study in Han Chinese. In the discovery stage, we analyzed 1,356,350 autosomal SNPs in 1,837 individuals with ankylosing spondylitis and 4,231 controls; in the validation stage, we analyzed 30 suggestive SNPs in an additional 2,100 affected individuals and 3,496 controls. We identified two new susceptibility loci between EDIL3 and HAPLN1 at 5q14.3 (rs4552569; P = 8.77 × 10(-10)) and within ANO6 at 12q12 (rs17095830; P = 1.63 × 10(-8)). We also confirmed previously reported associations in Europeans within the major histocompatibility complex (MHC) region (top SNP, rs13202464; P < 5 × 10(-324)) and at 2p15 (rs10865331; P = 1.98 × 10(-8)). We show that rs13202464 within the MHC region mainly represents the risk effect of HLA-B*27 variants (including HLA-B*2704, HLA-B*2705 and HLA-B*2715) in Chinese. The two newly discovered loci implicate genes related to bone formation and cartilage development, suggesting their potential involvement in the etiology of ankylosing spondylitis. 相似文献
179.
Ong CK Subimerb C Pairojkul C Wongkham S Cutcutache I Yu W McPherson JR Allen GE Ng CC Wong BH Myint SS Rajasegaran V Heng HL Gan A Zang ZJ Wu Y Wu J Lee MH Huang D Ong P Chan-on W Cao Y Qian CN Lim KH Ooi A Dykema K Furge K Kukongviriyapan V Sripa B Wongkham C Yongvanit P Futreal PA Bhudhisawasdi V Rozen S Tan P Teh BT 《Nature genetics》2012,44(6):690-693
Opisthorchis viverrini-related cholangiocarcinoma (CCA), a fatal bile duct cancer, is a major public health concern in areas endemic for this parasite. We report here whole-exome sequencing of eight O. viverrini-related tumors and matched normal tissue. We identified and validated 206 somatic mutations in 187 genes using Sanger sequencing and selected 15 genes for mutation prevalence screening in an additional 46 individuals with CCA (cases). In addition to the known cancer-related genes TP53 (mutated in 44.4% of cases), KRAS (16.7%) and SMAD4 (16.7%), we identified somatic mutations in 10 newly implicated genes in 14.8-3.7% of cases. These included inactivating mutations in MLL3 (in 14.8% of cases), ROBO2 (9.3%), RNF43 (9.3%) and PEG3 (5.6%), and activating mutations in the GNAS oncogene (9.3%). These genes have functions that can be broadly grouped into three biological classes: (i) deactivation of histone modifiers, (ii) activation of G protein signaling and (iii) loss of genome stability. This study provides insight into the mutational landscape contributing to O. viverrini-related CCA. 相似文献
180.
为探究植物性杀虫剂鱼藤酮、藜芦碱对蚯蚓的影响选择赤子爱胜蚓(Eisenia foetida)为受试生物,通过急性毒性实验和抗氧化酶活性测定,揭示鱼藤酮、藜芦碱的毒性效应。结果显示,急性染毒试验鱼藤酮对蚯蚓24h、48h的半致死质量浓度分别为23.96mg/L、5.991mg/L,藜芦碱对蚯蚓24h、48h的半致死浓度分别为40.67mg/L、20.33 mg/L。说明藜芦碱、鱼藤酮对蚯蚓有致死效应,鱼藤酮的毒性强于藜芦碱;蚯蚓体重的增长受到了药物浓度的影响,有较明显的剂量效应关系,但随时间的延长对蚯蚓体重的抑制效应减弱;在药物胁迫下,SOD与POD活性变化随质量浓度增大呈现先上升后下降,蚯蚓体内SOD、POD响应不同,POD对药物响应更敏感。 相似文献