Effects of ethylene biosynthesis and signaling on oxidative stress and antioxidant defense system in Nelumbo nucifera G. under cadmium exposure

Environmental Science and Pollution Research - Water contamination with cadmium (Cd) is a global environmental problem and its remediation becomes urgent. Phytoremediation using ornamental plants...     

膨润土造浆性能及加工工艺研究——以信阳膨润土为例

文章介绍了开发信阳膨润土使之成为钻井（探）用膨润土的研究过程。本文首先对具有代表性的膨润土进行了性能普查和评价，在此基础上添加复合碱对其进行升级改造，并对改造后的膨润土进行了室内评价，最后初步设计了一套膨润土生产流程     

印尼苏门答腊海域强震与广东地下水位响应特征研究

2004年以来印尼苏门答腊海域发生了4 次8.3 级以上巨大地震,广东地区地下水位观测记录到这4次地震的大量响应信息,归纳这些响应信息的表现形态、特征、及响应过程,获得响应强弱与震级大小之间的关系以及响应的"敏感点"等.通过总结这4次强震响应信息,有助于理解强地震的衰减过程和开展震源物理相关研究.     

Greenhouse gases emissions accounting for typical sewage sludge digestion with energy utilization and residue land application in China

About 20 million tonnes of sludge (with 80% moisture content) is discharged by the sewage treatment plants per year in China, which, if not treated properly, can be a significant source of greenhouse gases (GHGs) emissions. Anaerobic digestion is a conventional sewage sludge treatment method and will continue to be one of the main technologies in the following years. This research has taken into consideration GHGs emissions from typical processes of sludge thickening + anaerobic digestion + dewatering + residue land application in China. Fossil CO₂, biogenic CO₂, CH_4, and avoided CO₂ as the main objects is discussed respectively. The results show that the total CO₂-eq is about 1133 kg/t DM (including the biogenic CO₂), while the net CO₂-eq is about 372 kg/t DM (excluding the biogenic CO₂). An anaerobic digestion unit as the main GHGs emission source occupies more than 91% CO₂-eq of the whole process. The use of biogas is important for achieving carbon dioxide emission reductions, which could reach about 24% of the total CO₂-eq reduction.     

土壤水分管理对甲烷和氧化亚氮排放的影响

为控制农田温室气体排放的途径提供依据,通过实验室培养的方法测定了不同水分管理条件下CH4和N2O的排放,干旱处理（60％-70％WFP）和长期淹水土样在施肥后的Eh变化。最终得出：稻田CH4和N2O排放之间存在着互为消长的关系（R2=0．609）,CH4和N2O的排放是水肥共同作用的结果,水分管理通过Eh来影响气体排放,有机质是造成前后期排放浓度差异的主要原因。     

Inter-annual and intra-annual variations in water quality and its response to water-level fluctuations in a river-connected lake,Dongting Lake,China

Environmental Science and Pollution Research - The hydrological conditions of river-connected lakes are complex primarily owing to their considerable water-level fluctuations (WLFs). Water quality...     

Respiratory exposure to PM2.5 soluble extract induced chronic lung injury by disturbing the phagocytosis function of macrophage

Environmental Science and Pollution Research - Exposure to airborne urban particles is a contributing factor for the development of multiple types of respiratory diseases; its pathological role as...     

某省高危含砷爆炸物污染农田评价及分布研究

利用不同的评价标准和方法评价了吉林省某地含砷高危爆炸物造成的砷污染,同时借助GIS软件绘制了砷污染指数分布图。结果表明:以土壤环境背景值的上限值为评价标准,平均污染累积指数为2.61,最大为65.38,约57.38%的土壤受到人为外源砷的干扰;以(GB 15618-2008)中砷的二级标准作为评价标准,平均污染指数为1.01,最大污染指数达15.27,超标率为23.87%,表明该区存在严重的砷污染;地累积指数污染评价结果也表明该地存在明显的外源砷污染,受到污染的比例达41.57%;3种评价方法结果基本一致。污染指数分布表明,该地重污染区集中在中部区域,并形成了一个西北-东南方向分布的污染带。     

离子色谱法测定工业废水中丙酸

建立了用离子色谱法测定工业废水中丙酸的方法,结果表明,常规阴离子对本方法的测定没有干扰,校准曲线线性相关系数高,并且能在很大范围内呈现线性。运用该方法实测标样和水样,精密度和准确度都能满足需求,表明该方法测定结果可靠,具有一定的应用价值。对实际废水样品进行分析,丙酸的回收率分别为95．0％～103．8％。本方法分析速度快,所需样品量少,且无需要复杂的前处理,简便、灵敏、可靠。     

Is selenium deficiency really the cause of Keshan disease?

Keshan disease (KD) is a dilated cardiomyopathy closely related with a diet deficient in the mineral selenium. It is named for the northeastern Chinese county Keshan, where the disease prevalence is high because of selenium-deficient soil. KD is a gene–environment interaction disease. Here, we used stepwise multiple regression analysis to analyze the risk factors of the disease and the main clinical features in 71 KD patients and 290 controls. The variables analyzed included age, sex, family history of KD, blood selenium level, glutathione peroxidase-1 (GPx-1) activity, variance at codon198 in GPx-1 gene, residence in an endemic area, abnormal electrocardiography (ECG) findings, and cardiothoracic (CT) ratio. The main risk factors found were low GPx-1 activity, family history of KD and living in an endemic area. The main clinical features were increased cardiac load on ECG and increased CT ratio and Tei index. Public health and clinical prevention efforts could focus on increasing GPx-1 activity to address KD. Is selenium deficiency really the certain cause of KD? This is not at all a settled question. And further study is promptly required to investigate the etiology of KD.