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1.
Environmental Geochemistry and Health - The Caucasian mineral water (CMW) region is a unique area where mineral waters differ by their chemical composition and balneological properties. The...  相似文献   

2.
Geophagy, the deliberate consumption of soil, is a common practice amongst the world's poorer or more tribally oriented people of the tropics. An appraisal of three geophagical samples suggests that Fe is a mineral nutrient which can be supplied to humans in significant amounts via ingested soil. Geophagy provides a direct link between the geochemistry of soils and human health, but as yet this association has only a limited awareness amongst research workers.  相似文献   

3.
Peng  Hao  Guo  Jing  Li  Bing  Huang  Huisheng 《Environmental Chemistry Letters》2022,20(2):1249-1263
Environmental Chemistry Letters - Vanadium chemicals, known as the “vitamins of the modern industry,” are major resources widely used in the petroleum, steel, batteries and catalyst...  相似文献   

4.
Environmental Chemistry Letters - Heavy metal pollution such as water contamination by Pb, Hg, Cu, Cd and Cr ions is induced by rapid urbanization and industrialization and is a major threat to...  相似文献   

5.
Honey-bees, Apis, are an important model system for investigating the evolution and maintenance of worker sterility. The queen is the main reproductive in a colony. Workers cannot mate, but they can lay unfertilized eggs, which develop into males if reared. Worker reproduction, while common in queenless colonies, is rare in queenright colonies, despite the fact that workers are more related to their own sons than to those of the queen. Evidence that worker sterility is enforced by 'worker policing' is reviewed and worker policing is shown to be widespread in Apis. We then discuss a rare behavioural syndrome, 'anarchy', in which substantial worker production of males occurs in queenright colonies. The level of worker reproduction in these anarchic colonies is far greater than in a normal queenright honey-bee colony. Anarchy is a counterstrategy against worker policing and an example of a 'cheating' strategy invading a cooperative system.  相似文献   

6.
Season-dependent mineral accumulation was recorded in fruits of Okra and Tomato. The highest concentration was in summer in Okra and in winter in Tomato. Lowest concentrations were in winter in Okra and rainy in Tomato. Both crop plants indicated that the mineral contents were in the order of P > K > Ca > Mg > Na > Fe which also signify their relative functional importance in growth and metabolism.  相似文献   

7.
土壤与沉积物对多环芳烃类有机物的吸附作用   总被引:27,自引:0,他引:27  
吸附作用是疏水性有机物在土壤和沉积物环境中的重要迁移转化行为之一。多环芳烃是环境中一种重要的疏水性有机污染物。文章着重阐述了多环芳烃类有机物在土壤和沉积物中有机质和粘土矿物吸附机理,指出土壤、沉积物有机质的结构异质性是导致非线形吸附的重要原因;分析了影响多环芳烃吸附过程的诸多因素,并提出该研究领域存在的问题以及今后发展的方向。  相似文献   

8.
Yang  Sheng  Cheng  Yanping  Liu  Tong  Huang  Shaoping  Yin  Lihong  Pu  Yuepu  Liang  Geyu 《Environmental Chemistry Letters》2022,20(5):2951-2970
Environmental Chemistry Letters - During the Corona Virus Disease 2019 (COVID-19) pandemic, protective equipment, such as masks, gloves and shields, has become mandatory to prevent person-to-person...  相似文献   

9.
Titania (TiO2) has been the focus of attention of researchers since the first demonstration of its capability to generate the photocatalytic splitting of water into hydrogen and oxygen. However, there seems to be a recent surge in the research activity, involving modified TiO2 nanoparticles (NP), which are considered to be more effective due to different physicochemical properties in comparison to unmodified fine particle analogs. Several strategies have been employed to modify TiO2 to reduce recombination rates of photogenerated charge carriers to enhance the optimal functioning of TiO2. Doping with cations and anions and coupling it with another semiconductor are the most well-known modification methods used. Titania nanocomposites are known to have a plethora of applications. Photoexcitation of these particles are seen to be extraordinarily effective in eliciting microbial death which makes it an attractive candidate for the manufacturing of antimicrobial coatings. On the other hand, TiO2 induces the oxidation of various organic refractory compounds like tetracycline, sulfamethazine, and bisphenol. The photo-electrocatalytic oxidation technique which amalgamates the principle of photocatalysis and electrolysis serves as a newer, unswerving, and cost effective water treatment process. In the biomedical arena, use is now acknowledged for the photodynamic therapy of cancer, cell imaging, biological sensors, drug delivery system, and as endonucleases. In the commercial front, it is utilized in creams owing to its small particle size, which facilitates absorption through skin. It is also employed as ultraviolet blocking agents in sunscreen and commonly encountered as a brilliant white pigment in paint due to its brightness, high refractive index and resistance to discoloration. Its use in solar cells has also been reported. This review aims to encompass the new progress of modified TiO2 nanocomposites for efficient applications, emphasizing the future trends of TiO2 in arenas like healthcare, environment, biomedical, food, personal care, and pharmacy and also highlights the commercial implications of this promising nanomaterial.  相似文献   

10.
《Ecological modelling》2005,181(2-3):263-276
The extant 40 bison (Bison bison) constituting the Texas State Bison Herd (TSBH; USA) are directly and exclusively descended from a bison herd assembled by Charles Goodnight in the 1880s, representing a historically and genetically valuable resource. The population currently suffers from low genetic variation, low heterozygosity, high calf mortality, and low natality rates compared with other closed bison populations. Population viability analysis using the VORTEX program previously indicated a 99% chance of population extinction within the next 41 years [J. Mamm. 85 (2004) in press]. We developed a stochastic simulation model to evaluate the genetic and demographic consequences of various management scenarios for the TSBH using genotypic data from 51 microsatellite loci and demographic information recorded over a 6-year period. Our results reveal that without the introduction of new genetic variation, approximately 37% of the representative microsatellite loci will become fixed as the TSBH continues to lose genetic variation at a staggering rate of 30–40% within the next 50 years. Furthermore, if the current trends in natality and mortality rates continue, our model indicates the TSBH faces a 99% chance of extinction in the next 51 years. With the importation of unrelated male bison into the TSBH, and under the assumption of increased fitness, the probability of population survival in the next 100 years increases to 100%, and the population will reach the approximate carrying capacity of 200 bison in 15–16 years. Furthermore, our model predicts increases in genetic diversity and heterozygosity of 24.7–48.4% and 17.5–36.5%, respectively, in the next 100 years following the addition of new genetic variation. We conclude that the importation of bison into the TSBH is necessary to prevent extinction and ensure long-term population survival.  相似文献   

11.
The use of mineral and mineral-related wastes in road construction in Britain is reviewed. Only iron and steel slags have potential for use in road pavement layers and most wastes require modification before being suitable for sub-base construction. The principal outlet for wastes is as substitutes for bulk fill and the advantages and disadvantages of this use are considered. A dual-tendering system to assist decision making is described and results presented for its recent use in Britain.Crown Copyright 1979. Any views expressed in this paper are not necessarily those of the Department of the Environment or of the Department of Transport. Extracts from the text may be reproduced, except for commercial purposes, provided the source is acknowledged.  相似文献   

12.
Coastal areas of Iran are heavily affected by urbanisation, industrialisation, and maritime activities. One consequence of this environmental pressure is the contaminants accumulation, as heavy metals, into the marine ecosystem. In this review, the coastal areas in the north and south of the country were assessed for lead (Pb) contamination of, one of the most toxic metals found in the environment. All studies conducted during 2006–2016 with at least 10 specimens that reported the mean and standard deviation of Pb were considered in this review. Heterogeneity between studies was assessed using the Q and I2 statistics. The Pb mean concentration overall studies was estimated to be 21.88?µg/g (95% CIs: 16.25–27.50). Random effect model showed no statistical difference in mean Pb concentration levels between south and north coasts. However, the variability in Pb mean concentrations within southern coasts was considerable and statistically significant. Moreover, the Pb concentrations in the northern coasts of Persian Gulf and Oman Sea, in south of Iran, decreased in the following order Hormozgan > Khuzestan > Sistan-VA-Balluchestan > Bushehr while in the southern coasts of Caspian Sea, in north of Iran, decreased in the order Guilan > Mazandaran > Golestan.  相似文献   

13.
Free-ranging cervids acquire most of their essential minerals through forage consumption, though occasionally seek other sources to account for seasonal mineral deficiencies. Mineral sources occur as natural geological deposits (i.e., licks) or as anthropogenic mineral supplements. In both scenarios, these sources commonly serve as focal sites for visitation. We monitored 11 licks in Rocky Mountain National Park, north-central Colorado, using trail cameras to quantify daily visitation indices (DVI) and soil consumption indices (SCI) for Rocky Mountain elk (Cervus elaphus) and mule deer (Odocoileus hemionus) during summer 2006 and documented elk, mule deer, and moose (Alces alces) visiting licks. Additionally, soil samples were collected, and mineral concentrations were compared to discern levels that explain rates of visitation. Relationships between response variables; DVI and SCI, and explanatory variables; elevation class, moisture class, period of study, and concentrations of minerals were examined. We found that DVI and SCI were greatest at two wet, low-elevation licks exhibiting relatively high concentrations of manganese and sodium. Because cervids are known to seek Na from soils, we suggest our observed association of Mn with DVI and SCI was a likely consequence of deer and elk seeking supplemental dietary Na. Additionally, highly utilized licks such as these provide an area of concentrated cervid occupation and interaction, thus increasing risk for environmental transmission of infectious pathogens such as chronic wasting disease, which has been shown to be shed in the saliva, urine, and feces of infected cervids.  相似文献   

14.
土壤和地下水中多环芳烃生物降解研究进展   总被引:5,自引:0,他引:5  
多环芳烃是一类普遍存在于环境中的难降解的危险性"三致"有机污染物。受污染的土壤和地下水中的多环芳烃,生物降解是其归宿的主要途径。研究表明,对于土壤中低分子量多环芳烃类化合物,微生物一般以唯一碳源方式代谢;而大多数细菌和真菌对四环或四环以上的多环芳烃的降解作用一般以共代谢方式开始。文章重点论述了多环芳烃的来源、降解多环芳烃的微生物、生物降解机理、影响生物降解的因素以及生物修复方法。认为今后的研究方向是高分子量多环芳烃的降解机理与降解途径,基因工程技术在多环芳烃生物降解方面的应用,以及生物表面活性剂产生的机理及其在实际处理中的应用等。  相似文献   

15.
有机磷酸酯(organophosphate esters,OPEs)是使用最为广泛的有机磷阻燃剂,并兼具增塑剂、消泡剂和萃取剂等功能,被广泛用于电子产品、建筑材料和塑料材料等中,导致其在环境介质中普遍存在,对生态系统和人体健康构成巨大威胁.作为一种新型环境污染物,OPEs的人群暴露特征和生物毒性成为环境健康领域的研究热...  相似文献   

16.
India is one of the fluoride-endemic countries where the maximum numbers of ground or drinking water sources are naturally fluoridated. In India, a total of 23, out of 36 states and union territories have drinking water contaminated with fluoride in varying concentration. In the present scenario, especially in rural India, besides the surface waters (perennial ponds, dams, rivers, etc.), bore wells and hand pumps are the principal drinking water sources for domestic animals such as cattle (Bos taurus), water buffaloes (Bubalus bubalis), sheep (Ovis aries), goats (Capra hircus), horses (Equus caballus), donkeys (Equus asinus) and dromedary camels (Camelus dromedarius). Out of 23 states, 17 states, namely Andhra Pradesh, Assam, Bihar, Chhattisgarh, Gujarat, Haryana, Jharkhand, Karnataka, Kerala, Madhya Pradesh, Maharashtra, Odisha (Orissa), Punjab, Rajasthan, Telangana, Uttar Pradesh and West Bengal, have fluoride beyond the maximum permissible limit of 1.0 or 1.5 ppm in drinking water. This situation is a great concern for the animal health because fluoride is a slow toxicant and causes chronic diverse serious health hazards or toxic effects. Despite the fact that domestic animals are the basic income sources in rural areas and possess a significant contributory role not only in the agriculture sector but also in the strengthening of economy as well as in sustainable development of the country, research work on chronic fluoride intoxication (hydrofluorosis) due to drinking of fluoridated water in domestic animals rearing in various fluoride-endemic states is not enough as compared to work done in humans. However, some interesting and excellent research works conducted on different aspects of hydrofluorosis in domesticated animals rearing in different states are briefly and critically reviewed in the present communication. Author believes that this review paper not only will be more useful for researchers to do some more advance research work on fluoride-induced toxicosis in different species of animals but will also be helpful in the making of health policy for domestic animals at state and national level for the mitigation of hydrofluorosis in India.  相似文献   

17.
Environmental Geochemistry and Health - In the context of global climate change, understanding the relationships between climate and groundwater is increasingly important. This study in the NW Alps...  相似文献   

18.
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ABSTRACT

Carbon fiber-reinforced polymers (CFRPs) have attracted attention from the aerospace industry due to their light weight, excellent mechanical properties, and resistance to corrosion. However, CFRP composites are difficult to recycle as their recycling process must be performed under extreme conditions; end-of-life regulations do not directly address the problem with reusing these composites. Thus, the objective of this study is to explore solutions that minimize the use of CFRPs and prolong their useful life in the airline industry. To achieve this goal, this work conducted a review of the state of the art of CFRP fiber recycling, emphasizing the recycling processes, restrictions, and regulations. One solution is to develop a CFRP recycling market that would allow the sequential use of recycled materials among industries in descending order of the required structural performance of the composite.  相似文献   

20.
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