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91.
撬装式LNG汽车加气站结构设计   总被引:1,自引:1,他引:0  
介绍了撬装式LNG汽车加气站的基本结构设计及工作原理,着重对LNG加气站的3个主要系统包括储存系统、管路系统、控制系统进行了说明,并给出主要技术参数。分析了LNG加气站设备潜在的安全隐患,提出相关防范措施。实际运行表明,该加气站加气稳定、计量准确,各项指标符合设计要求。  相似文献   
92.
介绍了4种形式的天然气加气站:CNG标准站、CNG子母站、L-CNG加气站和LNG加气站的工艺流程和主要设备。通过对比各种加气站的建站成本和运营成本,采用差额投资财务内部收益率法对各种加气站建站方案进行经济性分析,并较为全面地从技术、设备、经济性和安全性方面给出了各种加气站的优缺点。指出今后在有条件的地区发展建设加气站应朝着L-CNG加气站和LNG加气站方向进行。  相似文献   
93.
碳酸盐岩储层流体包裹体差分拉曼光谱的研究   总被引:1,自引:0,他引:1  
Li J  Zha M 《光谱学与光谱分析》2010,30(9):2397-2400
拉曼微探针分析法对单个气液包裹体的化学成分和相态的无破坏性测量来说,目前几乎是唯一最好的方法.但是由于众多因素的影响,特别是主矿物具有较强荧光时,提高信噪比的问题急待解决.本工作对碳酸盐岩储层包裹体样品制成的薄片进行了显微观察、荧光测试及拉曼分析,并进行了空间上横向XY扫描、纵向上深度剖析(Z扫描)和冷热台上变温的流体包裹体筹分拉曼光谱测量方法的研究.结果表明,所得到的差谱揭示了包裹体更真实的光谱曲线,消除了主矿物对包裹体的干扰,以较高的信噪比显现出包裹体中流体(-170℃温度下的冰)位于位移波数3 098 cm-1附近的宽拉曼散射峰,明显的改善了信噪比.  相似文献   
94.
We study approximation problems for infinitely differentiable multivariate functions in the worst-case setting. Using a series of information-based algorithms as approximation tools, in which each algorithm is constructed by performing finitely many standard information operations, we prove that the L-approximation problem is exponentially convergent. As a corollary, we show that the corresponding integral problem is exponentially convergent as well.  相似文献   
95.
Poly(ethene-co-1-butene)-graft-methyl methacrylate-acrylonitrile (PEB-g-MAN) was prepared by suspension grafting copolymerization of methyl methacrylate (MMA) and acrylonitrile(AN) onto PEB. PEB-g-MAN/SAN resin blends (ABMS) were prepared by blending PEB-g-MAN with styrene-acrylonitrile copolymer (SAN resin). The effects of AN/(MMA+AN) feed ratio (fAN), PEB/(PEB+MMA+AN) feed ratio (fPEB) and benzoyl peroxide (BPO) dosage on the monomer conversion ratio (CR), rubber's grafting ratio (GR), grafting efficiency (GE) of the copolymerization and the toughening effect of PEB-g-MAN on the SAN resin were investigated. FTIR quantitative analysis showed that when the weight percent of AN unit in the unextracted product was 21.5 wt% with fAN of 25 wt%, the toughening effect of unextracted PEB-g-MAN on SAN resin was the highest. Gel permeation chromatography (GPC) analysis showed that when fAN was 25 wt%, the grafted copolymer had the lowest molecular weight and ABMS had highest toughness. Transmission electron microscopy (TEM) analysis showed that the highest toughness occurred when the phase structure of ABMS was cocontinuous with fAN of 25 wt%. When fAN was 25 wt% PEB-g-MAN domains have numerous small SAN domains in them, which was occlusion structure. Scanning electron microscopy (SEM) analysis indicated that the ABMS fracture surfaces had plastic flow visible, which looked like a craze fibers morphology, for the sample with highest impact strength (fAN = 25 wt%). Dynamic mechanical thermal analysis (DMA) showed that the miscibility of the PEB phase and SAN phase improved after graft copolymerization of MMA and AN onto PEB.  相似文献   
96.
EPDM-graft-methyl methacrylate and styrene (EPDM-g-MS) were synthesized by solution graft copolymerization of methyl methacrylate (MMA) and styrene (St) onto ethylene-propylene-diene terpolymer (EPDM). EPDM-g-MS/MS resin blends (MES) tht were prepared by melt blending EPDM-g-MS and methyl methacrylate-styrene copolymer (MS resin). The mechanical properties, compatibility, thermal stabilities and rheological properties of MES were studied by the pendulum impact tester and the tension tester, differential scanning calorimetric (DSC), thermogravimetry analysis (TGA), and the capillary rheometry, respectively. The results showed that EPDM-g-MS had an excellent toughening effect on MS resin; the notched Izod impact strength of MES reached 20.7 kJ/m2 when EPDM content in MES was 25 wt%, about 14 times that of MS resin. EPDM-g-MS and MS resin were partially compatible, and the compatibility increased with an increasing MMA/St ratio of EPDM-g-MS. MES had excellent heat-resistance, which increased as the EPDM content in MES and MMA/St ratio of EPDM-g-MS rose. MES melt flow confirmed pseudoplastic flow characteristics. The apparent viscosity (η a ) of MES decreased with an increasing shearing rate (γ) and temperature, but increased with an increasing EPDM content in MES and MMA/St ratio of EPDM-g-MS. The flow activation energy of MES was lower than that of MS resin.  相似文献   
97.
The mechanical properties of nano-single crystal gold and carbon nanotube-embedded gold (CNT/Au) composites under axial tension were investigated using molecular dynamics (MD) simulation method. The interactions between atoms were modeled using the many-body tight-binding (TB) potential and the empirical Tersoff potential coupled with the Lennard-Jones (L-J) potential. We get the yield strain and the yield stress of nano-single crystal gold 0.092, 5.74 GPa, respectively. The computational results show that the increase in Young's modulus of the long CNT-embedded gold composite over pure gold is much large. From the simulation, we also find that the yield stress and the yield strain of short CNT-embedded gold composite are evidently less than that of the nano-single crystal gold.  相似文献   
98.
研究了两纠缠原子与单模相干态光场相互作用系统中原子纠缠度的时间演化特性,运用全量子理论和数值计算的方法,应用Concurrence纠缠度量标准,讨论了原子初始时刻的纠缠状态和光场强度对两原子纠缠度的影响.结果表明:双原子系统初始纠缠度越大,两原子间的纠缠在演化过程中的峰值也越大;随着光场强度的增加,两原子纠缠度的振荡曲线逐渐表现出崩塌-回复现象,周期性也越来越明显.  相似文献   
99.
查新未  张淳民 《物理学报》2008,57(3):1339-1342
杨洪钦等提出一个用两个三粒子W态作为量子信道将N粒子GHZ态从发送者传送给两个接收者中任意一个的量子隐形传送方案. 给出其理论分析,并提出了一个仅用一个三粒子W态作为量子信道将N粒子GHZ态传送给两个接收者之一的量子隐形传送的方案. 关键词: 隐形传态 GHZ态 W态量子信道  相似文献   
100.
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