井旁地质界面的反射波模拟及f-k偏移成像研究

本文针对现有阵列声波测井仪器,对井旁不同角度和不同位置井旁地质界面的全波波列进行了物理和数值模拟。结果表明,在现有仪器源距范围内,可以从全波波形中观测到清晰的反射纵波。在此基础之上,针对阵列声波全波数据特点,对Stolt的f-k偏移方法进行了改进,使其更适应于阵列声波测井需要,该方法不受地质界面倾角的限制,而且一次可以有效地处理大量现场数据,可以分别得到上倾和下倾井旁地质界面图像。最后,应用该方法对一个倾斜井的阵列声波数据进行了处理,有效的得到了井旁地层界面成像图,验证了该方法的可靠性。     

热固印花浆工艺参数的优化

以PVC树脂和增塑剂邻苯二甲酸二辛酯(DOP)混合制备热固印花浆,主要探讨了增塑剂的用量、焙烘温度、焙烘时间对热固印花浆应用性能的影响.通过单因素分析可得制备最佳工艺为DOP用量选用范围在11.5mL～12.5mL之间(PVC树脂用量20g),最佳温度和时间是145℃和2min.     

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Impact of public name resolving services on Akamai

To enhance user perceived performance,Akamai＇ s content distribution network （CDN） utilizes the domain name system （DNS） effectively to redirect users to close-by content replicas over short time scale.The use of DNS redirection has brought a significant advantage to Akamai＇ s CDN.However,the reliance on DNS also poses a fundamental threat to Akamai＇ s content distribution model.In particular,systematic evaluation and quantification illustrates the impact of recent emerging public DNS resolving services on Akamai＇ s CDN,including the degradation of corresponding user perceived performance and the benefit damnification of collaborating internet services providers （ISPs） that host Akamai＇ s edge servers.The measurement demonstrates that a considerable penetration of public DNS resolving services （e.g.,OpenDNS and GoogleDNS） effectively corrupts the Akamai＇ s serving model,namely the large-scale server distribution and quick DNS redirection.     

Exploration on ecological regulation of the reservoirs

Reservoir regulation process in the Yangtze River basin is mainly divided into two types of flood regulation and initiating benefit regulation. The present reservoir management system and operation mode are mainly for dealing with or coordinating of flood control and benefit initiation as well as benefit distribution among various beneficial functions. From the view point of river ecosystem protection, the current regulation mode has two kinds of problems ： firstly, most of the reservoir regulation plans do not consider ecosystem protection at downstream of dams and needs of environment protection in reservoir areas; secondly, integrated regulation or management of water resources is ignored. It is very necessary to improve reservoir regulation mode, bearing problems faced by regulation of the Three Gorges reservoir and issues related to cascade development and regulation in Tuojiang and Minjiang River basins in mind. In accordance with the concept of scientific development, and the philosophy of ＂ensuring a healthy Yangtze River and promoting the harmony between human and water＂, taking flood control, benefit initiation and eco-system as a whole, this paper put forward the basic consideration to improve reservoir regulation as follows ： on the basis of requirements of ecosystem protection at downstream of dams and needs of environment protection in reservoir areas, we should bring the functions of reservoir such as flood control and benefit initiation into full play, control the negative influence to the ecosystem at downstream of dams and the environment in reservoir areas in an endurable scope, and restore the ecosystem and the environment step by step. This paper put forward the relevant regulation process aiming at the idiographic problems such as protection of ecosystem at downstream of dams and environment in reservoir areas, protection of aquatic wildlife species and fish species, regulation of sediment and protection of wetland.     

Simulated change in the near-surface soil freeze/thaw cycle on the Tibetan Plateau from 1981 to 2010

The near-surface freeze/thaw cycle in cold regions plays a major role in the surface energy budget,hydrological activity,and terrestrial ecosystems.In this study,the Community Land Model,Version 4 and a suite of high-resolution atmospheric data were used to investigate the changes in the near-surface soil freeze/thaw cycle in response to the warming on the Tibetan Plateau from1981 to 2010.The in situ observations-based validation showed that,considering the cause of scale mismatch in the comparison,the simulated soil temperature,freeze start and end dates,and freeze duration at the near-surface were reasonable.In response to the warming of the Tibetan Plateau at a rate of approximately 0.44°C decade-1,the freeze start-date became delayed at an area-mean rate of1.7 days decade-1,while the freeze end-date became advanced at an area-mean rate of 4.7 days decade-1.The delaying of the freeze start-date,which was combined with the advancing of the freeze end-date,resulted in a statistically significant shortening trend with respect to the freeze duration,at an area-mean rate of 6.4 days decade-1.Such changes would strongly affect the surface energy flux,hydrological processes,and vegetation dynamics.We also found that the rate of freeze-duration shortening at the near-surface soil layer was approximately 3.0 days decade-1lower than that at a depth of 1 m.This implied that the changes in soil freeze/thaw cycles at the near surface cannot be assumed to reflect the situation in deeper soil layers.The significant correlations between freeze duration and air temperature indicated that the shortening of the near-surface freeze duration was caused by the rise in air temperature,which occurred especially in spring,followed by autumn.These results can be used to reveal the laws governing the response of the near-surface freeze/thaw cycle to climate change and indicate related changes in permafrost.     

Discussion on the new space of strategic development and function of Hengsha,Shanghai

Integrating various resource advantages including location, land, coastline and waterway, Heng- sha, Shanghai will be the new space of strategic development in the future （especially after 2020）. Inspired by marine economic development and continual establishment for new strategic space of coastal cities, in this pa- per we will take the strategic development direction of Hengsha new space into consideration when enlarging on the positioning of the new development space in Hengsha, which includes international logistic center （free har- bor and logistic transshipment center）, modem port industry, high-end services, tourism, leisure, and recre- ation and ecological village in downtown area.     

The impacts of biofuels on food security and supply in China

Biofuels are the current promising alternative to fossil fuels. However, the fluctuating food prices caused by oil price led to critics to biofuels. The paper surveyed biofuels production and grain production and consumption demand, and come to the conclusion that there was a little impact of corn ethanol on international food price, and there was no impact on China＇ s food prices. China has launched non-food biofuels development strategy to use marginal lands for growing hard crops, such as sweet sorghum, tuber crops, and switchgrass etc. to produce biofuels without any impact on food security in the future.     

Heterosis and combining ability evaluation for growth traits of blunt snout bream （Megalobrama amblycephala） when crossbreeding three strains

The blunt snout bream(Megalobrama amblycephala)is a major aquaculture species in the Chinese freshwater polyculture system.In this study,complete diallel crossing of three strains(i.e.,Liangzi[LZ],Poyang[PY]and Yuni[YN])was used to evaluate the combining ability and heterosis effect of intraspecific crossbreeding on the growth performance(i.e.,body weight,total length,body length,body height,and Fulton’s coefficient of condition).The offspring produced from the three strains were reared in a communal pond for 20 months,and nine microsatellites were used to assess their pedigree.Of the749 offspring,708(94.53%)could be assigned directly to a single parental pair.Significant differences were observed in body weight(BW)among the different combinations,indicating that the combining ability of BW from each strain was significantly different.The general combining ability(GCA)of BW from the sire was much higher than that from the dam.The GCA for the dam and sire of the LZ and YN were the largest and the smallest,respectively.The special combining ability of YN$9 PY#was the largest,and YN$9 PY#showed significantly positive heterosis effects on all F1growth traits,except for Fulton’s condition coefficient(K)(P\0.05).In addition,significant positive linear correlations were found between the mean BW of corresponding progeny and the H E of the parental generation(y=600.7x-29.472,r=0.8651,P=0.0026),H O(y=1206.9x-518.14,r=0.7436,P=0.0216),and the polymorphism information content(y=1021.3x-331.31,r=0.8245,P=0.0063)as determined by a correlative test.The findings obtained from the study will be important for future considerations of M.amblycephala stock improvement programs.     

Mycelial fermentation and medicinal properties of a valuable medicinal fungus Cordyceps sinensis Cs-HK1

Cordyceps sinensis （Cs） or Dongchongxiacao in Chinese is a rare and precious medicinal mushroom. In this work, a Tolypocladium sp. fungus named Cs-HK1 was isolated from a natural Cs fruiting body, and its ultraviolet （UV）, infrared （IR） and high-performance liquid chromatography （HPLC） spectra all exhibited high degrees of matching to those of natural Cs, indicating the similarity of chemical composition. A crude polysaccharide （PS） fraction isolated from Cs-HKI fungal mycelium showed significant antitumor activity, inhibiting melanoma tumor growth in mice. The PS-treated mice showed significantly higher serum interferon-y （IFN-y） level and higher proliferation rate of lymphocytes ex vivo than the control animals, suggestive of the immunomodulatory activity of the PS fraction. In cell cultures, the PS fraction caused a significant and dose-dependent inhibitory effect on the proliferation of two cancer cell lines, B16/neu mouse melanoma and MDA-MB-231 human breast cancer cells, but not on normal spleen lymphocytes in vitro. Most of these bioactivities of the Cs- HK1 fungus were comparable to or even greater than those of natural Cs. The results showed that Cs-HK1 fungus may be a functional substitute for the natural Cs in health food and herbal medicine.     

基于超链接的Web社区研究

通过对Web页面的超链接分析来发现Web社区，构建了社区主题和成员的存储结构，用有无交叉子集两种情况来研究社区的组织体系，目的是为感兴趣的使用者提供有价值的且最可靠的、周期性的、最新的信息资源。     

Inactivation of Giardia by Ozone and Its Disinfect Mechanisms

This study was to investigate the effect of ozone(O3)inactivation on Giardia in water by the fluorescence staining method.In order to elucidate the dominant mechanisms of inactivation,cell surface or inner cell components damage were comparatively examined by scanning electron microscopy(SEM).Results suggested that O3had a stronger effect on inactivating capability.Firstly,when the concentration of O3was above 2.0 mg/L and the contact time was up to 5 min,it showed a significant inactivating effect.Secondly,the effect of turbidity on inactivation was also found to be significant in synthetic water;when turbidity increased,the inactivating effect decreased.Thirdly,the inactivating rates were improved with a temperature increase from 5 to 25℃,but decreased when the temperature were out of this range.The inactivating capability of O3was stronger under acidic conditions than alkalic conditions.Lastly,when the concentration of organic matter in the reactive system was increased,probably due to the competition between Giardia and organics on O3,the inactivating rate was decreased;in addition,the cellular morphology of Giardia varied with different contact times.At contact time of 30 s,cells were rotundity and sphericity;at 60 s they became folded,underwent emboly,and burst;and at 240 s,the cell membrane of Giardia shrinked and collapsed completely.     

Influence of Rare Earth Elements on Mechanical Properties and Corrosion Resistance of Cu-15Ni Alloy

In order to improve the mechanical property and Cl-+S2-corrosion resistance of B15 copper-nickel alloy,Cu-15Ni-xRE(x:0-0.1%by weight)alloy was prepared by adding rare earth(RE)in melted Cu-15Ni alloy using metal mould casting method.Optical microscopy(OM),electronic tensile testing machine,X-ray diffraction(XRD),scanning electron microscope(SEM),and electrochemical testing system were used to analyze mechanical property,corrosion resistance property,and surface microstructure of different treatment samples.The results of OM and tensile testing show that the RE addition can effectively deoxidize the alloy melt and the microstructure of the alloy changes from coarse dendrite to small equiaxed grain.By addition of 0.05%RE,the tensile strength and elongation of Cu-15Ni alloys are improved from 294 MPa to 340MPa,and 8%to 33.5%respectively.The results of electrochemical testing show that the corrosion resistance of Cu-15Ni alloy is greatly improved by adding proper amount of RE,whereas excess addition of RE worsens the corrosion resistance.The optimum RE content was about 0.05%by weight.In comparison with the alloy without RE,the corrosion potential and corrosion current density of Cu-15Ni alloy containing proper RE decreased by about-0.28 V and 70A/cm2,respectively.     

Building mechanism exploration of new deepwater terminal in Hengsha

To promote the construction of Shanghai international shipping center, the planneu new acepwatcr terminal construction in Hengsha pushes forward the innovation and breakthroughs of the existing port manage- ment system and building mechanisms. Through reviewing, analyzing, comparing and summarizing the suc- cessful experience of the major ports at home and abroad, market-oriented recommendations will be proposed in terms of effectiveness and feasibility, as well as the idea of＂Shanghai Freeport＂.     

China’s bioenergy industry development roadmap

Positive development of renewable energy, saving and substitution of fossil energy, promotion of the energy structure adjustment are the inevitable strategy choices of China＇ s sustainable development. This paper discussed the China＇ s bioenergy resources status, development targets and technology development roadmaps. China has 136. 140 million hm^2 of marginal land, which distribute mainly in western and northern regions. There are 1 billion t of crop residues and forestry waste annually, and 300 million t can be used to produce different kinds of bioenergies. And organic waste and manure can generate 50 billion m3 of biogas. The discussed development target indicated that it can construct a biomass oilfield with the capacity of 100 million t/year and reduce 200 million t of CO2 emission by 2020. The bioenergy technology development roadmap indicated that the bioethanol mainly uses non grain starch and hemicellulose products as raw materials in the near-term （2006 -2010）. The biodiesel technology will focus on the advanced production technology, FT diesel, liquefaction of biomass and raw material production technology.     

A simple spectroscopic method for the quantification of gold nanoparticle number concentration in water and fetal bovine serum solutions

In this work,we developed a facile and low-cost method with sufficient sensitivity for the quantitative determination of gold nanoparticles(GNPs)number concentration in water and fetal bovine serum solutions.The Au(III)digested from GNPs was reduced to Au(I)presumably by the thiol group of 2-mercaptobenzimidazole,then the Au(I)–thiolate complex was formed,the concentration of which is determined by absorbance at 300 nm.The number concentration of GNPs can be converted using microscopic images and simple calculations.The interference of serum can be avoided in this method.The limit of detection(LOD)of GNPs was calculated as 2.1 910-12mol/L in water solution and 1.3 9 10-11mol/L in fetal bovine serum(FBS)solution.This method provides a simple and fast way to determine the concentration of GNPs,which can be in carried out in the routine laboratory practice.