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1.
This paper is focused on the progress in the determination of water in glasses and melt inclusions with Raman spectroscopy. Using the presented ＂Comparator Technique＂ the water content of a sample is determined by siruple comparison with a known standard. A calibration curve is not necessary. Furthermore, with this technique the water concentration in silicate melt inclusions can be determined without exposing the inclusions for measurements. This is very important for extremely water-rich melt inclusions, which would loose H2O on exposure.  相似文献   

2.
Rainfall and air temperature data from six meteorological stations above the Bengbu Sluice and hydrological and water resources evaluation data from the Bengbu Hydrological Station in the Huai River Basin from 1961 to 2008 are used to analyze the impact of changes in climatic factors on the amount of water resources in the Basin. There was a general trend of rise in its average annual air temperature, with the highest increase of 0.289oC/10a recorded at Bengbu in Anhui Province. Rising rainfall was mainly observed in the western part of the study area, while rainfall actually declined in the eastern part, i.e. the middle reaches of the Huai River. The Average rainfall in the study area was in a vaguely declining trend. In other words, the rainfall in the Basin is still much affected by natural fluctuations. On the whole, there was a trend of gradual decrease in the quantity of the Basin’s water resources for the period under study. Water resources quantity is found to fall with decreasing rainfall and rising air temperature. Regression analysis is used to establish a mathematical model between water resources quantity and climatic factors (i.e. air temperature and rainfall) in order to explore the impact of climate change on water resources in the Basin. Moreover, various scenarios are set to quantitatively analyze the response of water resources to climate change. Sensitivity analysis shows that changes in rainfall have a much bigger impact on its water resources quantity than changes in its air temperature.  相似文献   

3.
A simple and reproduciable method for determining guanine by high performance capillary electrophoresis is presented. The method involved the use of 2-amino-5-mercapto-3,4-dithiazole as internal standard and 40mmol/L borax-H3PO4 (pH2)-5% EtOH as.the background electrolyte. The result showed that the linear range for guanine is 5-300 mg/L with the recovery of 94%-98% , the detection limit of 2. 80 mg/L and the RSD of 3. 1%. The satisfactory result was obtained when it was used to detect the concentration of guanine in acyclovir product.  相似文献   

4.
Vitamin D_2 and vitamin D_3 give a clear polarographic oxidation-wave,respectively,by neopolarography,with a 0.25M solution oflithium perehlorate in ethanol-dimethylformamide(1:1)as the supportingelectrolyte.Peak potentials are both+1.27V(vs.pure Ag plate).Thewave-height is proportional to the concentration in the range from 2.6×10~(-6)M(1μg/ml)to 1.1×10~(-3)M(420μg/ml)for vitamin D_3 and from2.5×10~(-6)M(1μg/ml)to 1.1×10~(-3)M(435μg/ml)for vitamin D_2,respe-ctively.The detection limits are both 1.3×10~(-6)M(0.5μg/ml).Themethod can be satisfactorily applied to the determination of vitamin D_3in injcction.Through various experiments,it is shown that the electrodeprocess of vitamin D at glassy carbon electrode is an irreversible oxida-tion process controlled by diffusion.The value of an is 0.84(α is thetransfer coefficient and n is the number of cleclron in the kineticprocess).n=2.The electrode reaction mechanism has been inferred.Besides,the choices of base solution and of experiment conditions aswell as the stability of vitamin D etc.are also discussed.  相似文献   

5.
The over-exploitation of water resources in the Haihe River Basin (HRB) has now become a serious problem. This is clearly evidenced by the fact that many local rivers and lakes are drying up and the total amount of over-exploited groundwater has reached over 1000×108m3. It is important to note that the exploitation of water resources in HRB was reasonable before 1979. After 1980, however, over-exploitation happened with an annual average amount of 40×108m3. Both the dry season and rapid economic growth in HRB took place at the same time. Therefore, the over-exploitation of water in HRB was actually the negative result of the conjunction of a continuous dry season and rapid economic growth. So the over-exploitation would not be as serious as it is today if either of the above two stopped. After the first stage of south-to-north water transfer project, the water shortage problem in HRB could be eased for the following reasons: fi rstly, water transfer project will bring to the Basin 60×108m3 water resources; secondly, a wet season will come back eventually according to natural law of climate variability; finally, its agricultural and industrial use and total water consumption all have decreased from the peak value, so that the groundwater table will raise certainly and ecological water in rivers and lakes that were dried-up will be partly restored. In the future, the main problem of water resources security in HRB will include water pollution, operation risk of the south-to-north water transfer project, groundwater pollution and engineering geological hazards that may be brought by groundwater rise. The proposed countermeasures are as follows: keeping strengthening water demand management, raising water price as well as subsidies for the low-income family and improving other water related policies, preventing and dealing with water pollution seriously and getting fully prepared for the operation of south-to-north water transfer project.  相似文献   

6.
In the arid regions of northwestern China, water is considered as the "life blood" of all living organisms and economic activities.An oasis will grow greener with ample supply of water, whereas the green will fade if water is in short supply. An inland river catchment constitutes an independent unit of ecological functions in which interactions and transformation occur between mountainous areas and plains, between oases and wastelands, and between ground surface runoffs and underground water. The sustainability of a catchment is deeply rooted in the coordination of hydrological, ecological and economical processes in a drainage basin.  相似文献   

7.
The vegetation in the transi-tional belts between theTaklimakan Desert and theoasis is not in the state of thirstyfor water as people thought, assertscientists of a Sino-EU project onsustainable management of the veg-etation in the foreland of oasis, andirrigation alone would not change thewater conditions of those plants.The key factor for a normal growthof the vegetation is to ensure a steadylevel of the underground water,which demands an intensifiedmanagement of water resources so asto ach…  相似文献   

8.
With continued population growth and accelerated industrialization and urbanization, water shortages and water quality deterioration have become a bottleneck restraining global socioeconomic progress. In China, water resources are unevenly distributed, with abundance in the south and scarcity in the north. Every year, a loss of nearly 100 billion yuan is incurred by water shortages in the north. The Middle  相似文献   

9.
Restoration forestry (forest rehabilitation) or re-vegetation is one effective measure to solve environmental problems, notably soil erosion. It may be further stimulated by the Clean Development Mechanism for carbon sequestration. However, there is an intensive and on-going debate about the adverse effects arising from afforestation in dryland areas, such as soil drying up which may cause further damage to the success of forest restoration, and the water yield reduction from watershed which may harm the regional development. On other hand, some preliminary studies showed a possibility that these adverse effects may be diminished more or less by properly designing the system structure and spatial distribution of forest/vegetation in a watershed. However, it is urgent to develop an evidence-based and sustainable new forestry policy for harmonizing forest-water interrelation. As a leading country in afforestation, China is beginning to develop a more trans-disciplinary and cross-sectoral forestry policy for harmonizing forestry development with water management. The main points of the changing new forestry policy should include: (1) Establishing a regional development strategy focusing on harmonized forest-water relations; (2) Taking forest-water interactions as an important part of evaluation; (3) Reducing the ’eco-water’ quota of forests through technical advancement; (4) Developing and extending water-adaptive forest management practices; (5) Strengthening forest ecohydrological research and decision support ability.  相似文献   

10.
The ecological water diversion project in the Heihe River Basin is the irst successful case in China in which the ecological systems in a river basin have been rescued. his project serves as a valuable example for the management of ecosystems in other inland river basins. his paper reviews the integrated studies of the water–ecosystem–economy relationship in the Heihe River Basin and concludes that sustainable development in inland river basins requires the basin to be considered as a whole, with the relationships between the upstream, midstream and downstream areas of the basin coordinated appropriately. Successful development in these basins will be relected in an improved output per cubic meter of water and the implementation of integrated river basin management practices.  相似文献   

11.
The Partner Group works on topics in geometric analysis in cooperation with the corresponding research group at the Max Planck Institute for Mathematics in the Sciences in Leipzig. The partnership is based on several years of collaboration between several research groups in China (the Chinese Academy of Sciences, Peking University, Fudan University, Wuhan University) and the group of Jurgen Jost in Leipzig. The group plays a pivotal role in the systematic advanced training of a whole generation of Chinese mathematicians. A particular focus is on variational problems from quantum field and superstring theories.  相似文献   

12.
The CAS Shenzhen Institute of Advanced Tech- nology (SIAT) is jointly founded by CAS and the gov- ernment of Shenzhen, China’s first special economic region. It is the first R&D entity in China specializing in modernized manufacturing and independent innovation with integrated technologies as its disciplinary orientation. Why SIAT? Involving a number of fields of sci- ence and engineering, the integrated technology has gained a rapid development and is recognized for a variety of app…  相似文献   

13.
Electroreduction of vitamin K3 provides the basis for research andsensitive determination of vitamin K3.The Single Sweep Oscillopolaro-graphy and Neopolarography are used to explore the interracial and redoxbehaviours.The detection limits are 5×10~(-9) M(1.75ng/ml),4×10~(-9)M(1.41ng/ml)respectively for the single sweep oscillopolarography andneopolarography.The linear responses of polarographic peaks againist theconcentration are all 1×10~(-8)-5×10~(-5)M.Both methods are used todemonstrate the electrode process and determination of vitamin K3 inpharmaccutics and plasma with a satisfactory result.  相似文献   

14.
<正>The highest good is like that of water.he goodness of water is that it beneits all the creatures;yet itself does not scramble,but is content with the places that all men disdain.It is this that makes water so near to Tao.—Tao Te ChingWATER IS IMPORTANT Water is a basic component of human existence,and people and ecosystems depend on it.It is one of the most fundamental requirements for the survival of  相似文献   

15.
Climate change will lead to a signifi cant alteration in the temporal and spatial pattern variation in the regional hydrological cycle, and the subsequent lack of water, environmental deterioration, floods and droughts etc. And it is especially remarkable in semi-humid and semi-arid region. In this paper, the impacts of climate change on the hydrological cycle were analyzed for the Hai River Basin, a semi-humid and semi-arid basin and also the water receiving area of the middle route of South-to-North Water Diversion Project. Meanwhile it is the most vulnerable to climate change. Firstly, the linear regression and Mann-Kendall non-parametric test methods were used to analyze the change characteristics of the hydrological and meteorological elements for the period from 1960 to 2009. The results show a signifi cant increase in temperature, while precipitation decreases slightly, and runoff decreases drastically over the past 50 years. Secondly, the applicability of SWAT (Soil and Water Assessment Tool) model based on the DEM (Digital Elevation Model), land use and soil type was verif ied in the basin. Results show the model performs well in this basin. Furthermore, the water balance model, Fu’s theory and Koichiro’s theory were used to calculate the actual evaporation, comparing to the simulated actual evaporation by SWAT model to validate the result for the lack of large-scale observed evaporation datasets. Possible reasons were also analyzed to explore the reasonable factor for the decline of the runoff. Finally the precipitation, temperature, runoff and evaporation response processes based on the IPCC AR4 multi-mode climate models and the verifi ed SWAT model under different GHG emission scenarios (SRES-A2, A1B and B1) in the 21st century were discussed in three time periods: 2020s (2011-2040), 2050s (2041-2070), 2080s (2071-2099). Results show that there are systematic positive trends for precipitation and temperature while the trends for runoff and evaporation will differ among sub-areas. The results will offer some references for adaptive water management in a changing environment, also including adaptation of a cross-basin water transfer project.  相似文献   

16.
This paper addresses the change of the river-lake relationship in the Huai River and its causes due to environmental change and human activities. A preliminary analysis is made from three aspects: (1) the natural geographical change particularly captured by the Yellow River, (2) water conservancy project construction, and (3) socioeconomic development in the Huai River Basin. Key problems of changes in this river-lake relationship and the Huai River flood control are tackled, involving flood control and disaster alleviation ability of the Basin, engineering and non-engineering measurements applied to flood control and disaster mitigation, and water governance for adaptive management. Research shows that the Huai River is a rather complex one due to its complex geography with a hybrid wet and dry climate zoon, and higher population density. With the alternation of the river-lake relationship and socioeconomic development in the region, new problems keep arising, imposing new requirements on its sustainable water management. Thus, understanding the Huai River is a long and gradually improving process. Its future planning should keep absorbing new achievements of science and technology development, employing new technologies and methods, and gradually deepening our understanding of its fundamental principles. Water governance and adaptive water management will be new challenges and opportunities for the Basin in its river system change and flood control.  相似文献   

17.
The Case in Brief The Perfetti Van Melle Corporation (the Perfetti Van Melle for short), an Italian company, registered three trademarks on sweets and candies in China respectively in January 1999, February 2002, and April 2002. The Perfetti Van Melle Sweets and Candies (China) Co., Ltd. (the Perfetti Van Melle (China) for short) is a sub-company set up with the Perfetti Van Melle‘s investment in 1994 in Shanghai, and is licensed to exclusively use the mother company‘s trade dress of the “阿尔卑斯(pronounced...  相似文献   

18.
The Case in Brief The Perfetti Van Melle Corporation (the Perfetti Van Melle for short), an Italian company, registered three trademarks on sweets and candies in China respectively in January 1999, February 2002, and April 2002. The Perfetti Van Melle Sweets and Candies (China) Co., Ltd. (the Perfetti Van Melle (China) for short) is a sub-company set up with the Perfetti Van Melle's investment in 1994 in Shanghai, and is licensed to exclusively use the mother company's trade dress of the "阿尔卑斯(pronounced as 'a er bei si' in the Chinese pinyin system) Alpenliebe" series of milk sweets (see Fig. 4) and said registered trademarks.  相似文献   

19.
Nearly 45% of the valid candidates for the new CASmembers in 2003 are unde60 years of age, a rise of about 10%if compared with that in 2001, according to a news release by theCAS Academic Divisions (CASAD)The CAS membership is thehighest academic title and an honoof life tenure conferred by the Statein Chinas S&T circles. The newmember election is held biennially.The procedure for the CASmember election this year started inJanuary. By April 30, 322 peoplesystems. After a scrutiny of…  相似文献   

20.
Agricultural S&T parks (ASTPs) constitute the bases for demonstrating modern agricultural practice engaged in intensive production and commercial operations with S&T achievements as their pillars and agricultural infrastructures as the mainstay. The emergence of ASTPs is a new economic phenomenon during the past decade, and among the 400-plus such parks, 36 are State ASTPs set up with the approval of the State Council. These ASTPs have created a benign environmental condition for the advance of agricultural science and technology in China and for the development of newand high-tech-based industries in the agricultural sector, and accordingly, they have played an important role in promoting modern agriculture, in enlivening rural economy, in increasing the income of farmers, and in restructuring agriculture.  相似文献   

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