141 resultados para GP shortage


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We measured the stable carbon isotope ratios for muscle of the upland buzzards (Buteo hemilasius), plateau pika (Ochotoma curzoniae), root vole (Microtus oeconomus), plateau zokor (Myospalax fontanierii) and passerine bird species at the Haibei Alpine Meadow Ecosystem Research Station (HAMERS), and provided diet information of upland buzzards with the measurement of stable carbon isotopes in tissues of these consumers. The results showed that δ~(13)C values of small mammals and passerine bird species ranged from -25.57‰ to -25.78‰ (n = 12), and from -24.81‰ to -22.51% (n = 43), respectively, δ~(13)C values of the upland buzzards ranged from -22.60‰ to -23.10‰ when food was not available. The difference in δ~(13)C values (2.88‰±0.31‰) between upland buzzards and small mammals was much larger than the differences reported previously, 1‰-2‰, and showed significant difference, while 1.31‰±0.34‰ between upland buzzard and passerine bird species did not differ from the previously reported trophic fractionation difference of 1‰-2‰. Estimation of trophic position indicated that upland buzzards stand at trophic position 4.23, far from that of small mammals, i.e., upland buzzards scarcely captured small mammals as food at the duration of food shortage. According to isotope mass balance model, small mammals contributed 7.89% to 35.04% of carbon to the food source of the upland buzzards, while passerine bird species contributed 64.96% to 92.11%. Upland buzzards turned to passerine bird species as food during times of shortage of small mammals. δ~(13)C value, a useful indicator of diet, indicates that the upland buzzards feed mainly on passerine bird species rather than small mammals due to "you are what you eat" when small mammal preys are becoming scarce.

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讨论了锻压机工作时偏心载荷对机架下横梁和立柱应力变化的影响程度,验证了下横梁的断裂原因;详细地讨论了导套筒对立柱作用反力的影响,指出了传统液压机设计方法中假设条件的不足,为该类机械的结构设计和改进提出了新的见解。

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研究资源受限系统动态调度问题,针对时序约束问题提出一种并行遗传算法(PGA)。给出满足排序优先次序约束的一种基因编码方法;采用不破坏优先级可行性的交叉操作,并予以证明;建立一种并行处理机制,使搜索避免出现局优现象。在技术允许情况下,单机动态调度引入抢占式加工方式,会一定程度上提高系统的性能。通过仿真试验验证,并行GA算法可兼顾优化效果和计算效率,解决单机动态调度问题。

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With the Oil field exploration and exploitation, the problem of supervention and enhaning combination gas recovery was faced.then proposing new and higher demands to precision of seismic data. On the basis of studying exploration status,resource potential,and quality of 3D seismic data to internal representative mature Oil field, taking shengli field ken71 zone as study object, this paper takes advantage of high-density 3D seismic technique to solving the complex geologic problem in exploration and development of mature region, deep into researching the acquisition, processing of high-density 3D seismic data. This disseration study the function of routine 3D seismic, high-density 3D seismic, 3D VSP seismic,and multi-wave multi-component seismic to solving the geologic problem in exploration and development of mature region,particular introduce the advantage and shortage of high-density 3D seismic exploration, put forward the integrated study method of giving priority to high-density 3D seismic and combining other seismic data in enhancing exploration accuracy of mature region. On the basis of detailedly studying acquisition method of high-density 3D seismic and 3D VSP seismic,aming at developing physical simulation and numeical simulation to designing and optimizing observation system. Optimizing “four combination” whole acquisition method of acquisition of well with ground seimic and “three synchron”technique, realizing acquisition of combining P-wave with S-wave, acquisition of combining digit geophone with simulation geophone, acquisition of 3D VSP seismic with ground seimic, acquisition of combining interborehole seismic,implementing synchron acceptance of aboveground equipment and downhole instrument, common use and synchron acceptance of 3D VSP and ground shots, synchron acquisition of high-density P-wave and high-density multi-wave, achieve high quality magnanimity seismic data. On the basis of detailedly analysising the simulation geophone data of high-density acquisition ,adopting pertinency processing technique to protecting amplitude,studying the justice matching of S/N and resolution to improving resolution of seismic profile ,using poststack series connection migration,prestack time migration and prestack depth migration to putting up high precision imaging,gained reliable high resolution data.At the same time carrying along high accuracy exploration to high-density digit geophone data, obtaining good improve in its resolution, fidelity, break point clear degree, interbed information, formation characteristics and so on.Comparing processing results ,we may see simulation geophone high-density acquisition and high precision imaging can enhancing resolution, high-density seismic basing on digit geophone can better solve subsurface geology problem. At the same time, fine processing converted wave of synchron acquisition and 3D VSP seismic data,acquiring good result. On the basis of high-density seismic data acquisition and high-density seismic data processing, carry through high precision structure interpretation and inversion, and preliminary interpretation analysis to 3D VSP seismic data and multi-wave multi-component seismic data. High precision interpretation indicates after high resolution processing ,structural diagram obtaining from high-density seismic data better accord with true geoligy situation.

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Today, because of high petroleum consumption of our country, society steady development and difficulty increase in new resources exploration, deep exploitation of the existing oilfield is needed. More delicate reservoir imaging and description, such as thin layer identification, interlayer exploitation monitoring, subtle structure imaging, reservoir anisotropy recognition, can provide more detail evidence for new development adjustment scheme and enhanced oil recovery. Now, the people have already realized the 3D VSP technique more effective than the general methods in solving these aspects. But VSP technique especially 3D VSP develop slowly due to some reasons. Carrying out the research of VSP technique, it will be very useful to the EOR service. 3D VSP techniques include acquisition、data processing and interpretation. In this paper, the author carried out some researches around acquisition and processing. The key point of acquisition is the survey design, it is critical to the quality of the data and it will influence the reservoir recognition as follows. The author did detailed researches on the layout pattern of shot point and geophone. Some attributes relate to survey design such as reflectivity, incidence angle, observation area, reflection points distribution, fold, minimum well source distance, azimuth angle and so on are studied seriously. In this geometry design of 3D-VSP exploration in deviated wells, the main problems to be solved are: determining the center position of shots distribution, the effect of shots missing on coverage areas and coverage times,locating the shots and receivers of multi-wells. Through simulating and analyzing, the above problems are discussed and some beneficial conclusions are drawn. These will provide valuable references to actual survey design. In data processing, researches emphasize on those relatively key techniques such as wavefield separation, VSP-CDP imaging, the author carried out deep researches around these two aspects. As a result, variant apparent slowness wavefield separation method developed in this article suit the underground variant velocity field and make wavefield separation well, it can overcome reflection bending shortage aroused by conventional imaging method. The attenuateion range of underground seismic wave is very important for amplitude compensation and oil/gas identification.In this paper, seismic wave attenuateion mechanism is studied by 3D-VSP simulateion and Q-inversion technique. By testing with seismic data, the method of VSP data attenuateion and relationship of attenuateion attribute variant with depth is researched. Also the software of survey design and data processing is developed, it fill the gap of VSP area in our country. The technique developed applied successfully in SZXX-A Oilfield、QKYY-B Oilfield、A area and B area. The good results show that this research is valuable, and it is meaningful to the VSP technique development and application of offshore oil industry and other areas in our country.

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Geopolymer gelatinous material was prepared by ferroalloy slag (signed with NKT in laboratory) and circulating fluidization bed slag (CFB slag, signed with NM in laboratory) produced from Heshan city, Guangxi zhuang autonomous region, China. The mechanical properties of the geopolymer made of high content ferroalloy slag can reach the standard of 42.5# portland blastfurnace-slag cement, and it’s processing technology is more simple and not need of mill and burn and will not produce harmful gas. By means of chemical and XRD analyses, it is concluded that NKT is a kind of acidity water-granulated slag with better activation and fit to be activated by alkali activators. Low-cost industrial gypsum (signed with NG in laboratory), analytic reagent oxide(signed with NH in laboratory) and sulfate(signed with NS in laboratory) were selected as alkali activation in the experiment. The results showed NH is a good alkali activator for NKT. Both NH and NG can activate ferroally slag’s activities, but NS can’t alone. The activation effect of superimposing activation of NH and NG excel by separateness. Based on those experiments, optimization compounds were carried out: (1) NKT: NH: NG = 80: 10: 10 and (2) NM: NKT: NS: NG: NH = 10: 70: 2: 8: 10。. The soundness of the test blocks is good by boiling examination. Through XRD, SEM, IR, NMR analyses of geopolymer, the reaction mechanism of geopolymer prepared by alkalescent activating in solid wastes was discussed in the thesis first. It is point out, there is difference in reaction mechanism between traditional geopolymer preparation and the preparation of alkalescent activating solid wastes because NG is a industry product. There is the similar process of depolymerization and reunion of Si-O bond. The latter preparation process generate new subtance but the former doesn’t. In the experiment, we found a performance of NKT that the water requirement of normal consistency of geopolymer reduces with increasing content of NKT. The result shows NKT has some ability to reduce water requirement. The performance is worthy of further research and utilization. Making use of solid wastes to prepare geopolymer, not only can settle environment problem caused by a great deal of dump of NKT, but also settle the shortage of natural resources. Moreover it could take economic, environmental and social benefits and settle thoroughly contradiction in the environment protection and regional economy development and promote circulation economy development.

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Data on seawater carbon isotope in the Mesoproterozoic and Neoproterozoic is abundant. However, the sulfur isotopic age curve of seawater sulfates determined through the analysis of sulfur isotopic composition of marine evaporite is uncertain in the Mesoproterozoic and Neoproterozoic since evaporites are generally rare in Precambrian. The Mesoproterozoic and Neoproterozoic Carbonate Formations preserve not only the carbon isotopic records, but also the sulfur isotopic records of coeval seawater in the Huabei Platform and the Yangtze Platform, China. Sulfur isotopic composition can be determined by the extraction of trace sulfate from carbonate samples. Successive measurements of sulfur and carbon isotopic compositions of carbonate samples from the Mesoproterozoic and Neoproterozoic strata in the Huabei Platform and the Yangtze Platform was accomplished through the extracting of trace sulfate from carbonates. Sulfur and carbon isotopic compositions of coeval seawater were obtained from analytical results of sulfur and carbon isotopes of the same sample without diagenetic alteration. The high-resolution age curve of sulfur isotope given in this paper may reflect the trend of variations in sulfur isotope composition of seawater sulfates during the Mesoproterozoic and Neoproterozoic. It can be correlated with the characteristics of variation in age curve of carbon isotope of coeval seawater carbonates. The δ34S values of seawater varied from +10.3-37.0‰ during the Mesoproterozoic, which took on oscillated variation on the whole. The δ34S values took on high values in the Mesoproterozoic Chuanlinggou stage, Tuanshanzi stage Tieling stage and in Neoproterozoic Jing'eryu stage. The average of those was about +30‰. The sulfates have low δ34S values in the Mesoproterozoic Yangzhuang stage and Hongshuizhuang stage, The average of those was all lower than +20‰. There occured large-amplitude changs in δ34S values of seawater during the Mesoproterozoic. Large-amplitude oscillate of 534S values occured in the intervals of 1600~1400Ma and 1300~1200Ma. The δ13C values of seawater are mostly negative in Changcheng stage of late Paleoproterozoic, -0 ± 1‰ range in Jixian stage of Mesoproterozoic , and the positive 2±2‰ commonly in early Neoproterozoic Jing'eryu stage. From 1000 Ma to 900 Ma, about 108 years interval of oceanic 513C record is shortage. At the end of Paleoproterozoic (1700 - 1600 Ma), the oceanic 813C values change from -3‰ to 0‰, but strongly oscillate near 1600 Ma. Two larger variations of seawater 513C values occur in the Mesoproterozoic: one is a cycle of about 4%o happens at ca. 1400 Ma; another is rise from >2‰ to>5‰ at ca. 1250 Ma and then become stable at the near 1000 Ma. There appears a large positive excursion over +20‰ in 534S value of ancient seawater sulfates in the early Doushantuo stage. Simultaneously, 8 C values of ancient seawater occur a positive excursion reaching 10‰. These allow δ4S values and 513C values to reach high values of+51.7‰ and +6.9‰, respectively. The range of variation in 834S values of seawater is relatively narrow and 513C values are quite high in the middle Doushantuo stage. Then, δ34S values of seawater become oscillating, the same happens in δ13C values. Negative excursions in 834S values and 813C values occur simultaneously at the end of the Doushantuo stage, and the minimum of δ34S values and δ13C values dropped to -11.3‰ and -5.7‰, respectively. The ancient seawater in the Dengying stage has high δS values and δ13C values. Most of the δ34S values of the trace sulfate samples varied between +23.6‰ and +37.9‰ except two boundaries of the Dengying Formation, and the S13C values of the carbonate samples of the Dengying Formation varied between +0.5‰ and +5.0‰. There appeared large negative excursion in 834S values and δ13C values of ancient seawater at the bounder of Precambrian-Cambrian. The isotopic characteristics of sulfur and carbon implicated that the organic productivity and isotopic fractionation caused by biology were low and the palaeoceanic environment was quite unstable during the Mesoproterozoic. The increase and subsequent oscillation of seawater δ13C value occurred from 1700 to 1600 Ma and near 1300 Ma may be responsible to the two global tectonic events happened at coeval time. The characteristics of variation in sulfur and carbon isotopes of ancient seawater imply strong changes in oceanic environment, which became beneficial to inhabitation and propagation of organism. The organic production and the burial rate of organic carbon once reached a quite high level during the Doushantuo stage. However, the state of environment became unstable that means the global climate and the environment possibly were fluctuating and reiterating after the global glaciation. The negative excursions of S34S values and δ13C values occurring at the end of the Doushantuo stage represent a global event, which might be relative to the oxidation of deep seawater. The isotopic characteristics of sulfur and carbon implicated that there were a high organic productivity and a high burial rate of organic carbon in the Dengying stage. It is obvious that the palaeoceanic environment in Dengying stage was stable corresponding and beneficial for biology to inhabit and propagate except for the two boundaries. The tendency of sulfur and carbon isotopic variations maybe resulted from the gradual oxygenation of ocean environment during the Dengying stage. It has been reported that the secular variations of the sulfur isotopic compositions in seawater was negative correlated with that of carbon isotopic compositions. However, our results show that it is not the case. They were negatively correlated in some intervals and positively in some other intervals of the Mesoproterozoic and Neoproterozoic. The difference in correlation may be associated with the changes in conditions of redox in oceanic environment, e.g. sharp change of the oxidation-reduction interface. The strong changes in global environment may induce the abnormality to occur in the biogeo chemical S and C cycles in the ocean and accordingly sharp Variations in isotopic composition of seawater sulfur and carbon during the Mesoproterozoic and Neoproterozoic. Simultaneously, the global tectonism caused large changes of 87Sr/86Sr ratios. The leading factor that causes the variation in isotopic composition is different in the different intervals of the Mesoproterozoic and Neoproterozoic. Thus, there may exist different models of the biogeochemical S and C cycles in the ocean during the Mesoproterozoic and Neoproterozoic.

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在1.0~4.0GPa压力、1073~1573K温度和10^-1~10^7Hz频率条件下,利用SARLTON-1260阻抗一增益/相位分析仪,就位测定了二辉橄榄岩的阻抗谱。实验结果表明:二辉橄榄岩的阻抗谱对频率具有很强的依赖性,并从阻抗谱的测试原理(颗粒内部、颗粒边缘、样品与电极间的导电机制)上做出了解释;温度是决定二辉橄榄岩电导率的一个重要物理参数,电导率随着温度的升高而增大,lgσ与1/T之间符合Arrenhius关系式;在高压实验中第一次将压力作为测量二辉橄榄岩电导率重要的约束因素,随着压力的增大,电阻率升高、电导率降低。

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Five hydrotalcites with Mg/Al molar ratio range of 3-15 were prepared. The structure and basicity of Mg-Al mixed oxides (Mg(Al)O) transformed from hydrotalcites were investigated by TPD, XPS, XRD, FT-IR and NMR techniques. The results of elemental analysis and XPS indicate that Al is enriched in the surface regions of Mg(Al)O, and its amount increases with the Mg/Al molar ratio and, the calcination temperature. Al-27-MAS-NMR results show that Al exists in two chemical environments: tetrahedral aluminium (Al(t)) and octahedral aluminium (Al(o)) in Mg(AI)O. The amount of Al(t) increases with the Mg/Al molar ratio and the calcination temperature. It is assumed that Al(t) may be mainly from the surface Al. Temperature-programmed desorption (TPD) of CO2 shows that the number of basic sites of Mg(Al)O samples increases with the Mg/Al molar ratio, and the maximum number of basic sites is obtained for hydrotalcite calcined at 773 K. Infrared spectra of adsorbed CO2 and B(OCH3)(3) reveal that there are two kinds of basic sites: weak basic OH- sites and strong basic O2- sites on the Mg(AI)O samples, the base strength depends on the Mg/Al molar ratio and calcination temperature.