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• Microstructure and solutes distribution of rapidly solidified Ti 50 Al 48 Mo 2 alloy was investigated. • Passivation film characteristics and forming mechanism of Ti 50 Al 48 Mo 2 alloy at different undercoolings were discussed. • Homogeneous solute distribution improved corrosion resistance of rapidly solidified Ti 50 Al 48 Mo 2 alloy. The rapid solidification of undercooled liquid Ti 50 Al 48 Mo 2 alloy was achieved by the electromagnetic levitation (EML) technique. At small and medium undercoolings, primary (βTi) dendrite reacted with surrounding liquid to drive a peritectic transformation into the (α Ti) phase. The solutal Mo and Al segregations were located within the dendrite center and the grain boundary during peritectic transformation, consequently B2 phase in the dendrite center and γ phase at the grain boundary formed. Once undercooling exceeded 253 K, the peritectic transformation was completely inhibited, and the formation of the B2 phase and γ phase was completely suppressed. The ultrafine eutectoid structure was formed and a complete solute trapping effect was realized. Homogeneous solute distribution facilitated the formation of thicker passivation film with lower defect density and higher film resistance on the alloy surface. Moreover, this weakened micro-galvanic effect reduced the susceptibility to pitting corrosion, and consequently the corrosion resistance of the alloy was improved. [ABSTRACT FROM AUTHOR]

Ti and its alloys have been widely applied in various fields of national economy due to their excellent combinations of specific mechanical properties and outstanding corrosion behavior. Among Ti alloys, Ti–1Al–8V–5Fe (Ti-185) alloy is a metastable and low-cost β-Ti alloy, and owns extremely outstanding mechanical performance. In the paper, to overcome the issue of β flecks associated with Fe segregation in conventional ingot metallurgy process, Ti-185 alloy was prepared by electrostatic levitation (ESL) technique at various supercoolings, and its solidification behavior and dendrite growth were systematically analyzed. Moreover, the thermophysical parameters of liquid Ti-185 alloy were tested, and the microstructure, hardness and compressive property were compared to that of cast ingot. Results shown that the maximum supercooling of 311 K in the liquid Ti-185 alloy can be achieved, and a noticeable recalescence phenomenon appears during ESL process. The density and the ratio of specific heat to emissivity of liquid Ti-185 alloy increases linearly with temperature decreasing. Once the crystal nucleus is formed, the nonfacted interface will advance promptly. Moreover, the dendritic growth velocity (v) exhibits an exponential relationship with the supercooling (ΔT), and can be depicted as the equation of v = 1.59·ΔT1.65 mm s−1. Additionally, at a supercooling of 229 K or above, single crystal can be formed using ESL technique. Furthermore, the microhardness, elastic modulus and compressive strength of as-levitated Ti-185 alloy are hardly affected by the supercooling, but the plasticity of as-levitated sample is obviously higher than that of as-cast one.

Electrostatic levitation technique and molecular dynamics simulation were performed to investigate the thermophysical properties, liquid structure and crystal growth dependence on undercooling of Ti85Ni10Al5alloy. The liquid Ti85Ni10Al5alloy was substantially undercooled up to 335 K (0.18TL). As undercooling increased, the potential energy of the liquid alloy decreased and the alloy entered into a high metastable state. At this state, the atoms tended to bond with each other and the clusters were inclined to convert into high-coordinated clusters, as confirmed by the fraction of the high-coordinated clusters variation. The enlarged clusters and enhanced local structure stability contributed to the increase of the thermophysical parameters and crystal growth velocity, and eventually dendrite refinement. The density, the specific heat and the surface tension of liquid alloy exhibited a linear relation with temperature and the shear viscosity of liquid alloy showed exponential variation which showed good agreement with the calculation results by molecular dynamics simulation. The growth velocity first increased slowly and then dramatically once the undercooling exceeded the threshold. The achieved maximum crystal growth velocity was 12.4 ms−1and it was up to 326 times of the value at 94 K undercooling.

The solute trapping effect and microhardness enhancement of quaternary Ni-5%Cu-5%Ag-5%Sn and quinary Ni-5%Cu-5%Ag-5%Sn-5%Ge alloys during rapid dendritic solidification are investigated by glass fluxing technique. In these two alloys, the experimental maximum undercoolings of 310 K (0.18TL) and 220 K (0.13TL) have been achieved and the rapidly solidified microstructures are composed of α(Ni) and (Ag) solid solution phases. The morphological transition from coarse dendrite into equiaxed structure is observed for α(Ni) phase with the increase of undercooling. The dendritic growth velocity of α(Ni) phase in quaternary Ni-5%Cu-5%Ag-5%Sn alloy is larger than that in quinary Ni-5%Cu-5%Ag-5%Sn-5%Ge alloy, which increases firstly and then decreases with the enhancement of bulk undercooling. The Vickers hardness of α(Ni) phase in these two alloys is enhanced with the increase of undercooling, which is attributed mainly to the grain refinement effect. Meanwhile, the solute trapping effect of Cu, Sn and Ge elements in the α(Ni) phase also contributes to the microhardness enhancement under large undercoolings. The addition of Ge element effectively increases the microhardness of α(Ni) phase due to solute strengthening mechanism.

A7R peptide (ATWLPPR), a ligand of the NRP-1 receptor, regulates the intracellular signal transduction related to tumor vascularization and tumor growth. Here, we designed A7R-cysteine peptide (A7RC) surface modified paclitaxel liposomes (A7RC-LIPs) to achieve targeting delivery and inhibition of tumor growth and angiogenesis simultaneously. The cytotoxicity, inhibiting angiogenesis, and internalization of various liposomes by cells were assessed in vitroto confirm the influence of the peptide modification. The accumulations of A7RC-LIPs in various xenografts in mice were tracked to further identify the function of the peptide on the liposomes’ surface. The results confirmed that A7RC peptides could enhance the uptake of vesicles by MDA-MB-231 cells, leading to stronger cytotoxicity in vitroand higher accumulation of vesicles in MDA-MB-231 xenografts in vivo. In addition, A7RC peptides enhanced the inhibitory effects of LIPs on the HUVEC tubular formation on Matrigel. The A7RC-LIPs may be promising drug carriers for anticancer therapy.

This paper introduces a way to build a model for a new kind of solution dehumidifier, and discusses the way to construct TRNSYS components for different kinds of solution dehumidifiers, and the factors that have the most important influence on the precision of the component have been presented. This paper contribute to the component library of TRNSYS, which will make TRNSYS capable to simulate THIC system.

More and more countries are focusing on the lack of resources with the consumption of large quantities of fossil energy. The Chinese government is actively promoting the policies related to the transformation of the energy structure which will increase the proportion of clean energy consumption and reduce the proportion of fossil energy consumption in order to relieve the pressure on domestic energy. Interest in the generation of biogas from agricultural residues is increasing rapidly due to its climate benefits. This article is committed to analysis the economic performance of the biogas cogeneration energy supply system of livestock and poultry breeding plants in southern China. The model of the biogas cogeneration energy supply system of livestock and poultry breeding plants in southern China and the advices to the government will also been proposed as a result. According to the results, biogas cogeneration system is feasible in economy with reasonable device configuration and operating strategy.

The MATH (meprin and TRAF-C homology) domain is a fold of seven anti-parallel -helices involved in protein- protein interaction. Here, we report the identification and characterization of 90 MATH-domain proteins from the Brassica rapa genome. By sequence analysis together with MATH-domain proteins from other species, the B. rapa MATH-domain proteins can be grouped into 6 classes. Class-I protein has one or several MATH domains without any other recognizable domain; Class-II protein contains a MATH domain together with a conserved BTB (Broad Complex, Tramtrack, and Bric-a-Brac) domain; Class-III protein belongs to the MATH/Filament domain family; Class-Iv protein contains a MATH domain frequently combined with some other domains; Class-V protein has a relative long sequence but contains only one MATH domain; Class-VI protein is characterized by the presence of Peptidase and UBQ (Ubiquitinylation) domains together with one MATH domain. As part of our study regarding seed development of B. rapa, six genes are screened by SSH (Suppression Subtractive Hybridization) and their expression levels are analyzed in combination with seed developmental stages, and expression patterns suggested that Bra001786, Bra03578 and Bra036572 may be seed development specific genes, while Bra001787, Bra020541 and Bra040904 may be involved in seed and flower organ development. This study provides the first characterization of the MATH domain proteins in B. rapa.

An accurate determination method of fatty acid methyl esters (FAMEs) in biodiesel produced from pistacia chinensis oil by gas chromatography (GC) was developed, with methyl tridecanoate used as an internal standard. The results show that the standard calibration curves for the FAMEs have good linearity over the concentration range, the linearity correlation coefficients (R2) are more than 0.99 for all the components. The average recoveries are from 95.26% to 99.66%. The method has good precision with the RSD ranging from 1.03% to 3.40%.

In the application of distributed generation technologies, different building have its own heat-to-power ratio, therefore equipment selection is a key point to determine the energy saving ratio. This study analyzes some devices of four different types, from two basic managements, heat-tracking and electricity-tracking. Result shows the optimal heat-to-power ratio of some certain devices and the changing trends were also given out. The energy saving ratio were also calculated.

In this paper, a model to optimize the system capacity size of the CCHP system based on a commercial software package LINGO is introduced and an illustrative example is presented. The model calculates the optimal size for the CCHP system applied in ST building and analyzes the variation trend of the annual cost saving ratio which is affected by the annual running and maintenance cost and annual investment cost. The influence of the energy price on the system is also be analyzed. When electricity price rises, the CCHP system is more economic than the conventional energy supply system. The CCHP optimal capacity size increases when electricity price rises. When natural gas price rises, the CCHP optimal capacity size decreases and it has poor economy.

According to the information of a large-scale public building in Shanghai, annual hourly loads of cooling, heating and power are calculated separately on the basis of Hourly Load Apportionment Ratio Method. Based on load characteristics and local practical condition, three cases are proposed for further comparison and selection by PRUE, ESR, CRR and PBP, and then the optimal case is to be determined. Moreover, the impact of installed capacity and gas price on the effect of applying CCHP system would be discussed. The result shows that both hotel and office area are appropriate for utilizing CCHP system; the combination of electro-refrigerator and absorption refrigerator is more economically preferable; PBP increases at first and then decreases while the capacity of electric generator rises, and when the capacity of generator and refrigerator are 4000kW and 4500RT, the PBP is lowest; The PBP will be 3 to 5 years if the price of natural gas could be fixed between 2.5 Yuan/m3 and 3Yuan/m3, which is a remarkable indicator of economical efficiency.

This paper first compares with international incentive policies, reviews some relevant incentive measures in China. Meanwhile, introduce the content of the critical subsidy policies in detail, summarize its positive impact on PV industrial development, and analyze a few of representative unreasonable problem in the process of policy application. Finally, gains some inspirations for the worldwide application of PV industry in China as follow: promotes the on-grid of building integrated PV (BIPV) projects, formulates rational feed-in tariff linking to the distinction of solar energy resources of different areas, which can ensure the profitability of PV industry in its operation period.

To fulfil the objective of high speed, high precision and intelligence in the modern equipment and advanced manufacturing industry, the magnetic bearing is requested to have small volume, low cost and low consumption. In this paper, an AC-DC three-degree-of-freedom hybrid magnetic bearing (AC-DC-3DOF-HMB) is studied, which integrates radial bearing and axial bearing in one of the magnetic bearing. The configuration and principle of AC-DC-3DOF-HMB are expounded, and the mathematical models of suspension forces are given. Then based on the function block diagram of AC-DC-3DOF-HMB control system, its hardware and software configuration are designed. The experiment results show that the rotor can be suspended stably with three degrees of freedom and has a good performance in anti- interference, and the feasibility of the control system design can be verified.

This paper optimizes the running strategy of residential cogeneration system, through discussing the introduction effect of a hypothetical cogeneration system for a detached house. Based on the seasonally electricity and thermal load characteristics, several annual running strategies were set considering the cogeneration equipment’s efficiency (electricity generation and thermal recover efficiencies). By simulating hourly operation condition, the yearly energy consumption, CO2 emission and energy cost were discussed. Then, the effect of running strategy were evaluated in the view of energy saving, energy cost and environmental effects. Analysis results is that the optimal running strategy is different for different co-generation equipment’s efficiency, and then the running strategy design should considering not only energy demand but also the equipment’s efficiency performance for residential cogeneration system.

This paper has examined the energy consumption characteristics for six different buildings including apartments, offices, commercial buildings, hospitals, hotels and educational facilities. Then 50000m2 development site for respective building’s type has been assumed as case study to evaluate the introduction effect of Combined Heat and Power (CHP). All kinds of CHP systems with different distributed generation technologies including Gas Turbine (GT), Gas Engine (GE), Diesel Engine (DE), Solid Oxide Fuel Cell (SOFC) and Polymer Electrolyte Fuel Cell (PEFC), have been simulated by using HEATMAP, CHP system analysis software. And their primary energy utilization efficiency, energy saving ratio and CO2 reduction ratio have evaluated and compared respectively. The results can be summarized as follows: various buildings have their special heat to power ratio characteristics. Matching the heat to power ratio demanded from an individual building with that supplied from a CHP system is very important. It is necessary to select a reasonable distributed generation technologies according to the load characteristics of various buildings. Distributed generation technologies with high energy generating efficiency and low heat to power ratio, like SOFC and PEFC is more reasonable selection for Building Combined Heat and Power (BCHP). CHP system is an attractive option for hotels, hospitals and apartments. The users can achieve high energy saving and environmental benefit by introducing a CHP systems. In others buildings, especially like commercial buildings and offices, the introduction of CHP system is unreasonable.

Saw palmetto (Serenoa repens) is the most commonly used herbal preparation in the treatment of benign prostatic hyperplasia. The objective of this study was to determine whether a characterized saw palmetto product affects the activity of cytochrome P450 (CYP) 2D6 or 3A4 in healthy volunteers (6 men and 6 women). The probe substrates dextromethorphan (CYP2D6 activity) and alprazolam (CYP3A4 activity) were administered orally at baseline and again after exposure to saw palmetto (320-mg capsule once daily) for 14 days. Dextromethorphan metabolic ratios and alprazolam pharmacokinetics were determined at baseline and after saw palmetto treatment. The mean ratio of dextromethorphan to its metabolite was 0.038 ± 0.044 at baseline and 0.048 ± 0.080 after 14 days of saw palmetto administration (P = .704, not significant [NS]), indicating a lack of effect on CYP2D6 activity. The area underthe plasma alprazolam concentration versus time curve was 476 ± 178 h · ng · mL−1at baseline and 479 ± 125 h · ng · mL−1after saw palmetto treatment (P = .923, NS), indicating a lack of effect on CYP3A4 activity. The elimination half-life of alprazolam was 11.4± 3.1 hours at baseline and 11.6 ± 2.7 hours after saw palmetto treatment (P = .770, NS), also indicating a lack of effect on CYP3A4 activity. Our results indicate that extracts of saw palmetto at generally recommended doses are unlikely to alter the disposition of coadministered medications primarily dependent on the CYP2D6 or CYP3A4 pathways for elimination. These conclusions must be weighed in the context of the study's limited assessments and regarded as only the initial investigation into the drug interaction potential of saw palmetto.Clinical Pharmacology & Therapeutics (2003) 74, 536–542; doi: 10.1016/j.clpt.2003.08.010

Garlic (Allium sativum L.) is a commonly used food and herbal supplement. The objective of this study was to assess in healthy volunteers (N = 14) the influence of a garlic extract on the activity of cytochrome P450 (CYP) 2D6 and 3A4. Probe substrates dextromethorphan (CYP2D6) and alprazolam (CYP3A4) were administered orally at baseline and again after treatment with garlic extract (3 × 600 mg twice daily) for 14 days. Urinary dextromethorphan/dextrorphan ratios and alprazolam plasma concentrations were determined by HPLC at baseline and after garlic extract treatment. The ratio of dextromethorphan to its metabolite was 0.044 ± 0.48 at baseline and 0.052 ± 0.095 after garlic supplementation. There were no significant differences between the baseline and garlic phases (P ≥ .05). For alprazolam, there were no significant differences in pharmacokinetic parameters at baseline and after garlic extract treatment (all P values ≥ .05; maximum concentration in plasma, 27.3 ± 2.6 ng/mL versus 27.3 ± 4.8 ng/mL; time to reach maximum concentration in plasma, 1.9 ± 1.4 h versus 2.4 ± 1.8 h; area under the time-versus-concentration curve, 537 ± 94 h · ng · mL−1versus 548 ± 159 h · ng · mL−1; half-life of elimination, 13.7 ± 4.4 h versus 14.5 ± 4.3 h). Our results indicate that garlic extracts are unlikely to alter the disposition of coadministered medications primarily dependent on the CYP2D6 or CYP3A4 pathway of metabolism.Clinical Pharmacology & Therapeutics (2003) 74, 170–177; doi: 10.1016/S0009-9236(03)00148-6

The present study was conducted to localize and characterize the subtype(s) of muscarinic receptor involved in prostacyclin (PGI2) production elicited by the cholinergic transmitter acetylcholine (ACh) in various cell types in the rabbit heart. ACh increased PGI2 synthesis measured as 6-keto-PGF1α, in cultured coronary endothelial cells and freshly dissociated ventricular myocytes in a dose dependent manner but not in cultured coronary smooth muscle cells of rabbit heart. McN-A-343, a partially selective M1 muscarinic ACh receptor (mAChR) agonist, did not alter 6-keto-PGF1α synthesis in these cell types. ACh induced 6-keto-PGF1α synthesis in coronary endothelial cells and ventricular myocytes was not altered by a low concentration (10-8 M) of pirenzipine, an M1 mAChR antagonist but was reduced by a higher concentration (10-6 M). In coronary endothelial cells ACh induced 6-keto-PGF1α production was reduced by hexahydro-sila-difendial (HHSiD), an M3 mAChR antagonist, and in ventricular myocytes by both 11-(2-[(di-ethylamino) methyl]-1-piperidinyl]acetyl-5,11-dihydro-6-H-pyrido-[2,3-b]-benzodiazepine-6 one] (AF-DX 116), an M2 receptor antagonist, and HHSiD. The decrease by ACh of isoporterenol stimulated cAMP accumulation was minimized by AF-DX 116 but not by HHSiD or pirenzipine. Pertussis toxin treatment minimized ACh induced decrease in isoproterenol stimulated rise in cAMP and ATP release, but not ACh induced 6-keto-PGF1α synthesis. These data suggest that ACh stimulates prostacyclin production in coronary endothelial cells via M3 mAChR and in ventricular myocytes M2 and M3 mAChR. Moreover, ACh induced decrease in cAMP, but not the increase in 6-keto-PGF1α production, is mediated by pertussis toxin sensitive Gαi proteins in these cells.

Wettability of liquid metal gallium is of vital significance in the field of modern industries, such as direct writing printing and microfluidics. A liquid interface is a recently developed and promising approach to regulate wettability but has not been well applied in liquid metals yet. This study focuses on the wetting performance of gallium droplets on organic liquid films. The results show that the organic liquid film could change the wetting state of the gallium droplet. Based on the solid substrate roughness and surface tension of the organic liquid, we could estimate whether the gallium droplet is in a slippery Wenzel or a Cassie state. Subsequently, we apply the thermodynamic stable model on different organic liquid films by spreading parameters to predict a priori whether an arbitrary combination of solid roughness and organic liquid is suitable for designing lubricant-infused surfaces (LIS) used in gallium droplets. More interestingly, we found that the “cloaking” could delay surface oxide formation, which will benefit the manipulation of liquid metal droplets. This paper would provide a better understanding of wettability of liquid metal on an organic liquid surface.

Not only is St. John’s wort of questionable value in treating depression, but it apparently can take part in dangerous drug interactions with a wide range of agents, including immunosuppressant drugs, amitriptyline, simvastatin, and digoxin. This study tested the possibility that St. John’s wort alters the activity of cytochrome P-450 (CYP) enzymes, which play a key role in drug metabolism. In an open-label crossover study, 6 healthy males and 6 females ranging in age from 22 to 38 years were assessed before and after receiving St. John’s wort for 2 weeks. Baseline activity of the P-450 enzymes CYP3A4 and CYP 2D6 was established by administering 2 mg alprazolam and 30 mg dextromethorphan as “probe” drugs. After a washout period of at least 1 week, the participants took 1 300-mg tablet of St. John’s wort 3 times daily for 14 days. Probe drugs were again administered along with 1 St. John’s wort tablet to quantify posttreatment CYP activity. The normal dosing regimen of St. John’s wort was continued for 48 hours. All subjects metabolized dextromethorphan extensively to dextrorphan, both at baseline and after St. John’s wort. The respective urinary ratios of dextromethorphan to its metabolite were 0.006 and 0.014. There was a 2-fold decrease in the area-under-the-curve for plasma alprazolam concentration versus time as well as a 2-fold increase in alprazolam clearance after 2 weeks on St. John’s wort. The mean elimination half-life dropped from 12.4 to 6.0 hours, a change significant at the 0.001 level. All participants had measurable levels of alprazolam at baseline, but this was true for only 7 of 12 participants after treatment. All subjects but 1 had measurable alprazolam at baseline, whereas none of them did after 48 hours. Similar findings were obtained for males and females. There were no significant changes in maximum plasma alprazolam concentration or the time to reach it. These findings suggest that long-term treatment with St. John’s wort could reduce the clinical efficacy or increase dose requirements for CYP 3A4 substrates, which represent half or more of currently marketed medications.

P-glycoprotein (P-gp) in the brain capillary endothelial cell limits the entry of many drugs into the brain. Our previous in-vitro study using ATPase as a marker of P-gp activity suggested that risperidone might be effectively transported by P-gp. In the present study, we compared the concentrations of risperidone and its major pharmacologically active metabolite 9-hydroxyrisperidone (9-OH-risperidone), in plasma, brain and various other tissues between abcb1ab-/- knockout mice which are functionally devoid of P-gp in their blood–brain barrier vs. FVB wild-type mice. One hour after intraperitoneal injection of 4 µg/g risperidone, the brain concentrations and ratios of brain:plasma concentrations of risperidone (13.1-fold and 12-fold respectively, p<0.05) and 9-OH-risperidone (29.4-fold and 29-fold respectively, p<0.01) were significantly higher in the abcb1ab-/- mice than those in the FVB mice. These results indicate that P-gp in the blood–brain barrier significantly influences the brain concentrations of risperidone and 9-OH-risperidone by limiting their CNS access.