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电解水制氢设备需要经常维护,定时检修,才能确保氢气的纯度和设备的安全。根据我台使用十多年来的经验与体会,现将该设备的常见故障及维修方法介绍如下,供台站同志参考。 1.造成氢气不纯的故障原因和排除的方法 (1)塑料槽盖焊缝裂开。电解水制氢设备运输到台站,要经过漫长路程的颠簸,尤其是公路运输装卸很容易将塑料槽盖的焊缝震裂。因此在新装或检修电解槽过程中,槽盖必须试漏。试漏的方法是把所有阳极杆全部拆下,将阳极杆的四个孔及氧气出气孔,用一节小木棍外套一节胶管将孔堵死,往氧室慢慢加水至加满为止,停留一段时间后,可检查各焊缝是否有水溢出。如发现焊缝有渗漏水现象,可用高强度凝固剂将缝隙补好。有条件的台站 相似文献
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目前,我国大多数高空气象台站仍沿用化学法制氢,推广电解水制氢的速度太慢,用电解水制氢的高空台站数量太少。现在是应该作出决策,淘汰化学法制氢的时候了。 化学法制氢的弊端是显而易见的:成本 相似文献
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Small heat shock proteins encompass a widespread but diverse class of proteins,which play key roles in protecting organisms from various stressors.In the present study,the full-length cDNAs of two small heat shock proteins(MgsHSP22 and MgsHSP24.1)were cloned from Mytilus galloprovincialis,which encoded peptides of 181 and 247 amino acids,respectively.Both MgsHSP22 and MgsHSP24.1 were detected in all tissues examined by real-time PCR,with the highest expression being observed in muscle and gonad tissues.The real-time PCR results revealed that Cd signifi cantly inhibited MgsHSP22 expression at 24 h and MgsHSP24.1 at 24 and 48 h under 5 μg/L Cd 2 + exposure.MgsHSP24.1 expression was also signifi cantly inhibited after 50 μg/L Cd 2+ exposure for 48 h.With regard to antioxidant enzymes,increased GPx and CAT activity were detected under Cd 2+ stress(5 and 50 μg/L),while no signifi cant difference in SOD activity was observed throughout the experiment.Overall,both MgsHsps and antioxidant enzymes revealed their potential as Cd stress biomarkers in M.galloprovincialis. 相似文献
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东海内陆架泥质区沉积物古菌群落垂向分布特征 总被引：1，自引：0，他引：1
为研究东海内陆架闽浙沿岸泥质区不同深度沉积物中古菌群落垂向分布特征, 利用古菌16S rDNA基因文库得到473个有效克隆、50个OTUs(Operational Taxonomic Units).16S rDNA序列系统进化和统计分析发现古菌分别归属于泉古生菌(Crenarchaeota)和广古生菌(Euryarchaeota), 其中以Miscellaneous Crenarchaeotic Group(MCG)为主, 仅含少量的Marine Benthic Group B(MBG-B)、South African Gold Mine Euryarchaeotic Group(SAGMEG)、Anaerobic Methanotrophs 3(ANME-3)、Marine Crenarchaeotic Group I(MG-I)和Marine Benthic Group D(MBG-D).该泥质区沉积物可能存在由ANME-3催化的甲烷厌氧氧化作用, 同源序列分析表明其古菌群落分布与周边环境有较大联系.UniFrac与沉积物环境因子分析表明该泥质区古菌群落垂向分布与沉积物有机质含量和粒度变化密切相关. 相似文献
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本研究依据2020年4月（春季）和2020年10月（秋季）珠江口海域的调查数据,根据“压力-状态-响应”（PSR）模型对珠江口海域进行富营养化状况评价,并通过主成分分析以及相关性分析来说明各环境因子对珠江口富营养化的影响。结果表明：在“优、良、中、差、劣”5个富营养化等级中,珠江口PSR综合评价等级为“差”等级,近几年内变化趋于稳定。有机污染物与营养盐对珠江口富营养化的影响较大,其次为叶绿素a和溶解氧。珠江口营养盐与盐度呈显著负相关,与叶绿素a呈显著正相关。周边城市的陆源排放输入是导致珠江口富营养化的主要因素,河口稀释混合作用以及浮游植物对珠江口的富营养化程度有影响。 相似文献
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脂多糖诱导的肿瘤坏死因子α(LITAF)是一种重要的转录因子,在调节LPS诱导炎症因子TNF-α的表达过程中发挥重要作用。采用表达序列标签(expressed sequence tags,ESTs)结合cDNA末端快速克隆技术(rapid amplification of cDNA Ends,RACE),获得了菲律宾蛤仔LITAF基因cDNA全长(VpLITAF),并利用实时荧光定量PCR技术研究VpLITAF的组织分布以及鳗弧菌、藤黄微球菌刺激下的时序表达特征。VpLITAF基因序列包含393bp的开放阅读框,编码130个氨基酸,预测分子量为14.39kD,理论等电点7.47。序列分析表明,VpLITAF具有高度保守的LITAF结构域,与其它贝类LITAF具有高度同源性,并在系统进化树中与海洋软体动物LITAF聚为一簇。VpLITAF基因主要表达于蛤仔肝胰腺,肌肉中的表达量则相对较低。鳗弧菌和藤黄微球菌刺激在某些时段可显著诱导VpLITAF基因的表达水平,最高可达对照组表达量的3.5倍,且鳗弧菌对VpLITAF基因表达的诱导作用明显强于藤黄微球菌。以上结果表明,VpLITAF在菲律宾蛤仔的固有免疫反应中发挥着重要作用。 相似文献
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Glutathione S-transferases (GSTs) are a class of enzymes that facilitate the detoxification of xenobiotics, and also play important roles in antioxidant defense. We identified two glutathione S-transferase isoforms (VpGSTS, sigma GST; VpGSTO, omega GST) from Venerupis philippinarum by RACE approaches. The open reading frames of VpGSTS and VpGSTO were of 612 bp and 729 bp, encoding 203 and 242 amino acids with an estimated molecular mass of 22.88 and 27.94 kDa, respectively. The expression profiles of VpGSTS and VpGSTO responded to heavy metals and benzo[a]pyrene (B[a]P) exposure were investigated by quantitative real-time RT-PCR. The expression of VpGSTS and VpGSTO were both rapidly up-regulated, however, they showed differential expression patterns to different toxicants. Cd displayed stronger induction of VpGSTS expression with an approximately 12-fold increase than that of VpGSTO with a maximum 6.4-fold rise. Cu exposure resulted in similar expression patterns for both VpGSTS and VpGSTO. For B[a]P exposure, the maximum induction of VpGSTO was approximately two times higher than that of VpGSTS. Altogether, these findings implied the involvement of VpGSTS and VpGSTO in host antioxidant responses, and highlighted their potential as a biomarker to Cd and B[a]P exposure. 相似文献
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