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1.
Using the quasiregular model, some characteristics of the phase diagram with a minimum point were studied for a binary system. We obtained the inequalities which must be satisfied by these parametera WS,WL,VS and VL in various models.  相似文献   
2.
A projectile ion-recoil ion coincidence technique has been employed to study the multiple ionization and the charge transfer processes in collisions of 60–120 MeV Si q+ (q = 4−14) ions with neutral argon atoms. The relative contribution of different ionization channels, namely; direct ionization, electron capture and electron loss leading to the production of slow moving multiply charged argon recoil ions have been investigated. The data reported on the present collision system result from a direct measurement in the considered impact energy for the first time. The total ionization cross-sections for the recoil ions are shown to scale as q 1.7/E p 0.5 , where E p is the energy in MeV of the projectile and q its charge state. The recoil fractions for the cases of total- and direct ionizations are found to decrease with increasing recoil charge state j. The total ionization fractions of the recoils are seen to depend on q and to show the presence of a ‘shell-effect’ of the target. Further, the fractions are found to vary as 1/j 2 upto j = 8+. The average recoil charge state 〈j〉 increases slowly with q and with the number of lost or captured electrons from or into the projectile respectively. The projectile charge changing cross-sections σ qq are found to decrease with increasing q for loss ionization and to increase with q for direct-and capture ionization processes respectively. The physics behind various scaling rules that are found to follow our data for different ionization processes is reviewed and discussed.  相似文献   
3.
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies. Coupled channel calculations incorporating couplings to 2+ and 3 states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies.  相似文献   
4.
研究一维热传导方程热源反问题.给出基于最小二乘支持向量机(LS-SVM)求解的半解析表达式,此外还给出一种参数调节方法以及算法稳定性的证明.数值实验表明该方法具有较高的数值精度和稳定性.  相似文献   
5.
在原子能院串列加速器上,利用束箔方法,测量了能量为30 MeV Fe离子产生的高剥离态谱线跃迁结构的寿命值.在30 MeV时,Fe通过箔膜的电荷态分布在7+到17+,我们选择Fe XⅥ2p~6(~1S)4p—2p~6(~1S)5d(~2P_(3/2)~o—~2D_(3/2))的谱线,谱线波长124.696(?),能级寿命为79±4 ps.最后对实验误差进行了分析.  相似文献   
6.
为研究影响碳基吸附剂吸附超临界温度气体的主要因素,选择石墨化热解碳黑BP280和Ajax活性炭,分析超临界温度高压甲烷在其上的吸附平衡。应用容积法,在压力0~20.5 MPa、温度253 K~313 K测定甲烷的吸附平衡数据,并由等量吸附线标绘和亨利定律常数确定等量吸附热。引入通用吸附等温方程,再由方程的Langmuir标绘确定最大吸附容量,进而通过方程的线性化计算吸附平衡态中甲烷分子的作用能。结果表明,甲烷在两种吸附剂上的最大吸附容量均随温度而变化,并都小于液态甲烷的密度;甲烷在碳黑和活性炭上的等量吸附热分别为11.9 kJ/mol~12.5 kJ/mol和17.5 kJ/mol~22.5 kJ/mol,体现了两种吸附剂不同的表面能量分布;甲烷分子间作用能随吸附量的变化特点反映了超临界温度甲烷以类似于压缩气体状态聚集的特点和吸附剂结构上的差异。碳基吸附剂的比表面积和微孔容积是影响其储存甲烷容量的重要因素。  相似文献   
7.
This paper describes a novel method to map guanine bases in short oligonucleotides using a simple chemical modification reaction and subsequent analysis by electrospray ionization ion trap mass spectrometry (ITMS). In situ guanine-specific methylation followed by gas-phase fragmentation permits the determination of the positions of all guanine residues. Collision-induced dissociation (CID) of the monomethylated oligonucleotide strand promotes rapid depurination and further collision (MS3) of the apurinic oligonucleotide leads to preferential cleavage of the backbone at the site of depurination. The mass of the resulting complementary product ions verifies the position of each guanine base in the sequence. The utility of this methodology is demonstrated for oligonucleotide sequences up to 10 bases in length. In addition, this technique successfully illustrates the use of selective fragmentation for sequencing oligonucleotides by ITMS.  相似文献   
8.
It is known that the problem of minimizing total weighted completion time on a series-batching machine is NP-hard. We consider a series-batching bicriteria scheduling problem of minimizing makespan and total weighted completion time with equal length job simultaneously. A batching machine can handle up to b jobs in a batch, where b is called the batch capacity of the machine. We study the unbounded model with b≥n, where n denotes the number of jobs. A dynamic programming algorithm is proposed to solve the unbounded model, which can find all Pareto optimal schedules in O(n3) time.  相似文献   
9.
The Mekong River (MR) is the major water source in Southeast Asia, sharedby six countries. There is a rush, by riparian states, to acquire sources of alternative energy and other benefits to meet growing demands for water and energy. China and Myanmar have refused to cooperate fully in the MR Forum, leading to increase risks within the region. Development of the water resources of the MR Basin is the subject of intense debate both within the Mekong region and internationally. This paper investigates the concept of issue linkage to resolve unidirectional externalities in the MR. Using linked games, the paper shows that the downstream nations can consider the use of linkage as a form of side payment in achieving a basin‐wide agreement. While this approach supports the Integrated Water Resource Management‐based Basin Development Strategy adopted by the Mekong River Commission in April 2011 for managing the region's sustainability development, facts on the ground suggest that traditional issues to be linked may not be sufficient. The paper addresses this observation and suggests a cadre of issues, including nontraditional ones, to be analyzed in a future work.  相似文献   
10.
A simple design for an in situ, three-electrode spectroelectrochemical cell is reported that can be used in commercial Q- and W-band (ca. 34 and 94 GHz, respectively) electron paramagnetic resonance (EPR) spectrometers, using standard sample tubing (1.0 and 0.5 mm inner diameter, respectively) and within variable temperature cryostat systems. The use of the cell is demonstrated by the in situ generation of organic free radicals (quinones and diimines) in fluid and frozen media, transition metal ion radical anions, and on the enzyme nitric oxide synthase reductase domain (NOSrd), in which a pair of flavin radicals are generated.  相似文献   
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