引汉济渭工程地质灾害风险预测

陕西省引汉济渭工程属于跨流域大型水利工程,5个单元工程呈线状跨越构造剥蚀山地和断陷盆地,工程地质性质差异大,易发生地质灾害。实地调查地质灾害点共72处,其中滑坡66处,崩塌3处,泥石流3处。现状评估认为地质灾害危险性中等13处,其余59处均为危险性小。预测评估认为工程本身可能遭受31处地质灾害威胁,危险性小28处,危险性中等3处;工程建设可能加剧地质灾害39处,危险性小36处,危险性中等3处;工程建设可能引发地质灾害30处,危险性小15处,危险性中等15处。综合评估工程主要位于危险性小的区段,受地质灾害危害不大,风险较低。     

Measurement of HONO flux using the aerodynamic gradient method over an agricultural field in the Huaihe River Basin, China

To investigate nitrous acid(HONO) levels and potential HONO sources above crop rotation fields. The HONO fluxes were measured by the aerodynamic gradient(AG) method from 14 December 2019 to 2 January 2020 over an agricultural field in the Huaihe River Basin. The ambient HONO levels were measured at two different heights(0.15 and 1.5 m), showing a typical diurnal cycle with low daytime levels and high nighttime levels. The upward HONO fluxes were mostly observed during the day, whereas deposition...     

柴油车尾气颗粒物净化用SiC过滤材料的研究与应用

近年来,SiC材料作为一种新型的柴油车尾气颗粒物过滤材料获得了迅速发展,正逐步取代目前广泛应用的堇青石多孔陶瓷材料.结合堇青石和SiC过滤材料的性能特点,重点概述了2种SiC改性过滤材料(重结晶SiC.RSiC和硅结合SiC,Si-SiC)的研究和应用进展,并介绍了SiC颗粒物过滤器的市场现状和发展前景.     

Effect of TRF1 rs3863242 polymorphism on telomere length in omethoate-exposed workers

Abstract

Telomere length was found to be associated with omethoate exposure and polymorphisms in certain genes among occupational workers. However, whether the polymorphisms in telomere-binding protein genes influence telomere length remains unclear. To explore the correlation between telomere length and polymorphisms in telomere-binding protein genes, telomere length in peripheral blood leukocytes was determined by real-time quantitative polymerase chain reaction in 180 omethoate-exposed workers and 115 healthy controls. Polymorphisms in 10 pairs of alleles were detected using flight mass spectrometry or polymerase chain reaction–restriction fragment length polymorphism technique. The results showed that individuals with GG genotype in TRF1 rs3863242 had longer telomere lengths than those with AG?+?AA genotype in the control group (p?=?0.005). The multiple regression analysis suggested that both omethoate exposure (b?=?0.526, p?<?0.001) and TRF1 rs3863242 GG (b?=?0.220, p?=?0.002) were related to a longer telomere length. In conclusion, GG genotype in TRF1 rs3863242 is linked to prolongation of telomere length, and individuals with GG genotype are recommended to strengthen health protection in a Chinese occupational omethoate-exposed population.     

熔盐蒸发器管板封口焊缝泄漏原因分析

某光热电站熔盐蒸发器入口侧管板封口焊缝发生泄漏,通过表面检测和观察,发现裂纹是从封口焊缝根部发展,并从根部向外扩展的。根据裂纹扩展方向和运行数据进行综合分析认为,熔盐蒸发器在未正确操作下导致在极短时间内管板下部表面升温过快,造成封口焊缝局部热应力过大。在焊缝残余应力、工作应力和热应力共同作用下,管板下部封口焊缝根部产生裂纹并扩展至焊缝表面,形成贯穿性裂纹,造成蒸发器管板泄漏。     

Research on targeted land poverty alleviation patterns based on the precise identification of dominant factors of rural poverty: a case study of Siyang County,Jiangsu Province,China

Environment, Development and Sustainability - Poverty is a common problem faced by various social and economic forms. Eliminating poverty is a major issue of common concern and research all over...     

“阳光体育”背景下学校体育管理变革利益分析

从"阳光体育"助推学校体育管理变革出发,借鉴和运用利益相关者理论,分析我国学校体育管理变革的逻辑基础以及划分出不同的利益相关者,指出学校体育管理变革实质上就是各利益相关者之间利益博弈或行为协作的制度变迁过程,其结果是各利益相关者对学校体育资源及其附属品的再分配,其中利益冲突是变革的核心内容,而造成利益冲突的原因是多方面的。走向利益均衡是学校体育管理变革的基本价值取向。     

A field study of the relationship between sulfide-bound metals and bioaccumulation by Limnodrilus sp. in a heavily polluted river

Acid volatile sulfide (AVS) has been regarded as an important factor controlling metal bioavailability in anoxic sediments, but its effect on metal accumulation under natural conditions is poorly understood. Here, a field study of the influence of AVS on metal accumulation by Limnodrilus sp. in a heavily polluted river is provided. Most of the study area was subject to anaerobic and strongly reducing conditions, and the concentration of trace metals in surface sediments was high, as were the concentration of AVS and simultaneously extracted metals (SEM; average AVS?=?20.3 μmol g^?1, average ∑SEM₅?=?9.42 μmol g^?1; ∑SEM₅ refers to the sum of SEM_Cd, SEM_Cu, SEM_Pb, SEM_Ni, and SEM_Zn). Only a few species and small quantities of benthic invertebrates were found, and Limnodrilus sp. was dominant. There was no correlation between trace metal accumulation and (SEM-AVS), and in stations where (SEM-AVS) <0, the absolute value of bioaccumulation was high (average ∑BIO₅?=?4.07 μmol g^?1; ∑BIO₅ refers to the sum of BIO_Cd, BIO_Cu, BIO_Pb, BIO_Ni, and BIO_Zn), indicating that there was no relationship between (SEM–AVS) and metal accumulation in Limnodrilus sp. This was likely because Limnodrilus sp. ingest sediment particles as their main food source, so pore water metals play a minor role in their bioaccumulation (BIO) of materials. However, ∑BIO₅ was significantly correlated with ∑SEM₅ (r?=?0.795, p?<?0.01), revealing that the large number of sulfide-bound metals (SEM) in sediments may play an important role in metal accumulation in Limnodrilus sp., which can assimilate sulfide-associated metals by the help of the digestive fluids in the digestive systems.     

Grey optimization Verhulst model and its application in forecasting coal-related CO2 emissions

Environmental Science and Pollution Research - Energy saving and emission reduction are the most concerned issues in the world. Objective and accurate prediction of carbon emissions can provide...     

Environmental significance of biogenic elements in surface sediments of the Changjiang Estuary and its adjacent areas

Biogenic elements and six phosphorus(P) fractions in surface sediments from the Changjiang Estuary and adjacent waters were determined to investigate the governing factors of these elements, and further to discuss their potential uses as paleo-environment proxies and risks of P release from sediment. Total organic carbon(TOC) and leachable organic P(Lea-OP) showed high concentrations in the estuary, Zhejiang coast and ofshore upwelling area. They came from both the Changjiang River and marine biological input.Biogenic silicon(BSi) exhibited a high concentration band between 123 and 124°E. BSi mainly came from diatom production and its concentration in the inshore area was diluted by river sediment. Total nitrogen(TN) was primarily of marine biogenic origin. Seaward decreasing trends of Fe-bound P and Al-bound P revealed their terrestrial origins. Influenced by old Huanghe sediment delivered by the Jiangsu coastal current, the maximum concentration of detrital P(Det-P) was observed in the area north of the estuary. Similar high concentrations of carbonate fluorapatite(CFA-P) and CaCO3 in the southern study area suggested marine calcium-organism sources of CFA-P. TOC, TN and non-apatite P were enriched in fine sediment, and Det-P partially exhibited coarse-grain enrichment, but BSi had no correlation with sediment grain size. Diferent sources and governing factors made biogenic elements and P species have distinct potential uses in indicating environmental conditions. Transferable P accounted for 14%-46% of total P. In an aerobic environment,there was low risk of P release from sediment, attributed to excess Fe oxides in sediments.