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The microstructure and mechanical properties of Ti-3.5Al-5Mo-6V-3Cr-2Sn-0.5Fe high strength titanium alloy sheets prepared by unidirectional cold rolling and two-step cross cold rolling were investigated. Results showed that the β phase grains were refined significantly by cold rolling followed by solution treatment for a short time.Compared to unidirectional cold rolling, the short time solution treatment after two-step cross rolling could significantly reduce the non-uniformity of the microstructure of the alloy sheets. After aging treatment at 550 ℃,the anisotropy of the mechanical properties still existed in the unidirectional rolled sheets, and the tensile strength was highest along the rolling direction. After solution and aging treatment, the anisotropy of the mechanical properties of the two-step cross rolling process sheet was not obvious than unidirectional cold rolling,and alloy had good strength and plasticity matching.  相似文献   
4.
The biodiversity, geographic distribution, and community parameters of the benthic tanaidaceans associated with three coral reefs along the SW and SE Gulf of Mexico were analysed. A total of 15,525 specimens were grouped in 36 species. The highest value of abundance was found in the PNSAV with 6382 tanaidaceans. The PNSAV presented 30 species, the ANPT-L 16 species, and the SABS 17 species. The species with the widest distribution were Pseudonototanais sp., Condrochelia dubia, Leptochelia forresti, Synapseudes sp., Haplopolemius propinquus, Alloleptochelia longimana, and Paradoxapseudes bermudeus. In the Veracruz System Reef, the highest abundance was recorded for Condrochelia dubia and Pseudonototanais sp. The highest value of diversity was obtained in the SABS (3.08 bits/ind in the reef Bajo Diez), and the lowest value was found in the PNSAV (0.07 bits/ind in the reef Isla de Enmedio). The highest value of abundance was found in coral rubble and macroalgae. A significant relationship between depth and specific richness was found in the three reef systems. Using cluster analysis, three groups were found in each system, mainly related to the proximity to the coast and to urban areas. This is one of the first studies to show the specific substrate and attributes of three communities of tanaidaceans along the SE–SW coast of the Gulf of Mexico.  相似文献   
5.
N,N-Diallyl methionine ethyl ester hydrochloride 5 underwent alternating copolymerization with SO_2 via the Butler cyclopolymerization protocol in dimethyl sulfoxide(DMSO) to give water-soluble cycloterpolymer 6 with a ~1:1 molar ratio of sulfide and sulfoxide groups as a result of oxygen transfer from DMSO. Half of the sulfide groups in 6, upon oxidation with H_2O_2, afforded polymer sulfoxide 7 and polymer sulfone 8. The solution properties of these polymers were determined via a viscometric technique. The thermal stability of these polymers was determined by thermogravimetric analysis. The inhibition efficiency obtained from gravimetric mass loss, potentiodynamic polarization, and electrochemical impedance spectroscopy techniques agreed well with each other. The corrosion efficiencies increase with increasing concentration of the polymers. At a polymer concentration of 175 mM, the maximum inhibition efficiency of copolymer compounds 6–8 was determined to be 92%, 97%, and 95%, respectively. The synthesized polymer compounds acted as mixed-type inhibitors. Polymer compound 7 adsorbed onto the metal surface via chemisorption and physisorption and obeyed Langmuir, Temkin, and Freundlich adsorption isotherms. Analyses by X-ray photoelectron spectroscopy and scanning electron microscopy–energy-dispersive X-ray spectroscopy indicated that the adsorbed polymers formed a thin film on the metal surface and prevented further corrosive attack.  相似文献   
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Weldments were produced using gas tungsten arc welding(GTAW) and pulsed current gas tungsten arc welding(PCGTAW) techniques with ERNiCr-3 filler wire. Macro examination revealed that the resultant weldments were free from defects. A refined microstructure was observed in the weldment fabricated through PCGTAW. Scanning electron microscopy(SEM) analysis revealed secondary phases in the grain boundaries. Energy-dispersive X-ray spectroscopy(EDS) analysis revealed that microsegregation of Cr carbide precipitates was completely eradicated through PCGTAW. The microsegregation of Nb precipitates was observed in the GTA and PCGTA weldments. X-ray diffraction(XRD) analysis revealed the existence of M_(23)C?_6 Cr-rich carbide and Ni_8Nb phases in the GTA weldments. By contrast, in the PCGTA weldments, the Ni_8Nb phase was observed. The Cr_2Ti phase was observed in both the GTA and the PCGTA weldments. Tensile tests showed that the strength and ductility of the PCGTA weldments were slightly higher than those of the GTA weldments.  相似文献   
7.
开发了一套原料处理量为25 kg/h的两步进气下吸式固定床气化系统,并对两步进气直筒形(Stratified)下吸式固定床气化炉的炉型、结构和主体尺寸以及焦油检测系统进行了设计,对鼓风机、引风机、出炭螺旋等关键部件的参数进行了计算。气化炉整体高度为2683 mm,气化炉有效内径为350 mm,所需引风量和鼓风量都是60 m3/h。采用木片为原料,通过冷态实验和热态实验对气化系统进行验证,验证了该气化系统完全满足设计和实验需要。通过对比两步进气和一步进气实验结果,发现两步进气法可有效提升炉体温度,显著提高可燃气中可燃气体组分含量和热值,并有效降低可燃气中焦油含量。  相似文献   
8.
Computer experiments are constructed to simulate the behavior of complex physical systems. Uniform designs have good performance in computer experiments from several aspects. In practical use, the experimenter needs to choose a small size uniform design at the beginning of an experiment due to a limit of time, budget, resources, and so on, and later conduct a follow up experiment to obtain precious information about the system, that is, a sequential experiment. The Lee distance has been widely used in coding theory and its corresponding discrepancy is an important measure for constructing uniform designs. This paper proves that all the follow up designs of a uniform design are uniform and at least two of them can be used as optimal follow up experimental designs. Thus, it is not necessary that the union of any two uniform designs yields a uniform sequential design. Therefore, this article presents a theoretical justification for choosing the best follow up design of a uniform design to construct a uniform sequential design that involves a mixture of ω≥ 1 factors with β_k ≥ 2, 1 ≤ k ≤ωlevels. For illustration of the usage of the proposed results, a closer look is given at using these results for the most extensively used six particular cases, three symmetric and three asymmetric designs, which are often met in practice.  相似文献   
9.
G-protein-coupled receptors (GPCRs) can constitute complexes with non-GPCR integral membrane proteins, while such interaction has not been demonstrated at a single molecule level so far. We here investigated the potential interaction between the thyrotropin receptor (TSHR) and the monocarboxylate transporter 8 (MCT8), a member of the major facilitator superfamily (MFS), using fluorescence cross-correlation spectroscopy (FCCS). Both the proteins are expressed endogenously on the basolateral plasma membrane of the thyrocytes and are involved in stimulation of thyroid hormone production and release. Indeed, we demonstrate strong interaction between both the proteins which causes a suppressed activation of Gq/11 by TSH-stimulated TSHR. Thus, we provide not only evidence for a novel interaction between the TSHR and MCT8, but could also prove this interaction on a single molecule level. Moreover, this interaction forces biased signaling at the TSHR. These results are of general interest for both the GPCR and the MFS research fields.  相似文献   
10.
Multicellular organisms contain numerous symbiotic microorganisms, collectively called microbiomes. Recently, microbiomic research has shown that these microorganisms are responsible for the proper functioning of many of the systems (digestive, immune, nervous, etc.) of multicellular organisms. This has inclined some scholars to argue that it is about time to reconceptualise the organism and to develop a concept that would place the greatest emphasis on the vital role of microorganisms in the life of plants and animals. We believe that, unfortunately, there is a problem with this suggestion, since there is no such thing as a universal concept of the organism which could constitute a basis for all biological sciences. Rather, the opposite is true: numerous alternative definitions exist. Therefore, comprehending how microbiomics is changing our understanding of organisms may be a very complex matter. In this paper we will demonstrate that this pluralism proves that claims about a change in our understanding of organisms can be treated as both true and untrue. Mainly, we assert that the existing concepts differ substantially, and that only some of them have to be reconsidered in order to incorporate the discoveries of microbiomics, while others are already flexible enough to do so. Taking into account the plurality of conceptualisations within different branches of modern biology, we will conduct our discussion using the developmental and the cooperation–conflict concepts of the organism. Then we will explain our results by referring to the recent philosophical debate on the nature of the concept of the organism within biology.  相似文献   
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