Synthesis of Intermetallic Compounds by Using Lithium Hudride

Intermetallic compounds of AB 5 type are promising materials for M-H batteries. In this report we present the results about the influence of quality of intermetallic compounds prepared by a new method of synthesis on their electrochemical properties. The well-known intermetallic Ln 1-xM xNi 5-yMe y (Ln=La, Mm; M=Zr; Me=Mn, Ge, Sn, Al, Co+Sn, Co+Ge) compounds were synthesized by using mixtures of oxides, chlorides and carbonates of metals by interaction with lithium hydride at 700～1000 ℃. Prepared samples have the uniform microstructure with average dimension of particles about 20～30 μm. Electrochemical tests show that kinetic behaviour of compositions are satisfactory under current up to 200 mA·g -1. These compositions require practically no activation and limiting values of the discharge capacity were reached at 2～3 cycle up to 300 mAh·g -1, which can be considered as most promising for practice.

Absorbed Bioactive Compounds Replicate GuanxinⅡ-Induced Endothelium-Associated in/ex vivo Vasodilation

Objective:To develop an interference-free and rapid method to elucidate GuanxinⅡ(GXⅡ)'s representative vasodilator absorbed bioactive compounds(ABCs)among enormous phytochemicals.Methods:The contents of ferulic acid,tanshinol,and hydroxysafflor yellow A(FTA)in GXⅡ/rat serum after the oral administration of GXⅡ(30 g/kg)were detected using ultra-performance liquid chromatography-mass spectrometry.Totally 18 rats were randomly assigned to the control group(0.9%normal saline),GXⅡ(30 g/kg)and FTA(5,28 and 77 mg/kg)by random number table method.Diastolic coronary flow velocity-time integral(VTI),i.e.,coronary flow or coronary flow-mediated dilation(CFMD),and endothelium-intact vascular tension of isolated aortic rings were measured.After 12 h of exposure to blank medium or 0.5 mmol/L H_(2)O_(2),endothelial cells(ECs)were treated with post-dose GXⅡof supernatant from deproteinized serum(PGSDS,300μL PGSDS per 1 m L of culture medium)or FTA(237,1539,and 1510 mg/m L)for 10 min as control,H_(2)O_(2),PGSDS and FTA groups.Nitric oxide(NO),vascular endothelial growth factor(VEGF),endothelin-1(ET-1),superoxide dismutase(SOD),malondialdehyde(MDA)and phosphorylated phosphoinositide 3 kinase(p-PI3K),phosphorylated protein kinase B(p-AKT),phosphorylated endothelial nitric oxide synthase(p-e NOS)were analyzed.PGSDS was developed as a GXⅡproxy of ex vivo herbal crude extracts.Results:PGSDS effectively eliminates false responses caused by crude GXⅡpreparations.When doses equaled the contents in GXⅡ/its post-dose serum,FTA accounted for 98.17%of GXⅡ-added CFMD and 92.99%of PGSDS-reduced vascular tension.In ECs,FTA/PGSDS was found to have significant antioxidant(lower MDA and higher SOD,P<0.01)and endothelial function-protective(lower VEGF,ET-1,P<0.01)effects.The increases in aortic relaxation,endothelial NO levels and phosphorylated PI3K/Akt/e NOS protein induced by FTA/PGSDS were markedly abolished by NG-nitro-L-arginine methyl ester(L-NA,e NOS inhibitor)and wortmannin(PI3K/AKT inhibitor),respectively,indicating an endothelium-dependent vasodilation via the PI3K/AKT-e NOS pathway(P<0.01).Conclusion:This study provides a strategy for rapidly and precisely elucidating GXⅡ's representative in/ex vivo cardioprotective absorbed bioactive compounds(ABCs)-FTA,suggesting its potential in advancing precision ethnomedicine.

Degradation products of different water content sevoflurane in carbon dioxide absorbents by gas chromatography-mass spectrometry analysis

Background Sevoflurane is currently used as a volatile inhalation anesthetic with many clinical advantages. A representative degradation product, compound A, was quantitatively measured to investigate whether there are different reactions between two kinds of water content sevoflurane formulations with different carbon dioxide （CO2） absorbents.

A Strategy for Detecting Absorbed Bioactive Compounds for Quality Control in the Water Extract of Rhubarb by Ultra Performance Liquid Chromatography with Photodiode Array Detector

Objective： To detect absorbed bioactive compounds of the water extract whose pharmacodynamic effect was craniocerebral protection for quality control assessment. Methods： Anthraquinones in water extract of rhubarb （WER）, in cerebrospinal fluid （CSF） of patients with traumatic brain injury （TBI） and in ipsilateral cortex of TBI rats following oral WER were respectively explored by ultra performance liquid chromatography with photodiode array detector （UPLC-PDA） method developed in the present study. The effects of anthraquinones absorbed into injured cortex on superoxidase dismutase （SOD） activity in TBI rats were detected. The antioxidative anthraquinones absorbed into target organ were evaluated for quality control of WER. Results： Anthraquinones in WER were aloe-emodin, rhein, emodin, chrysophanol, and physcion. Only the last anthraquinone was found in CSF and in ipsilateral cortex under this chromatographic condition. Physcion increased SOD activity in TBI rats significantly. Conclusions： Physcion was the main active compound of rhubarb against craniocerebral injury via antioxidant pathway. According to our strategy, the exploration of physcion suggested the possibility of a novel quality control of WER in treating TBI injury.

Variations in Growth, Photosynthesis and Defense System Among Four Weed Species Under Increased UV-B Radiation

Weed tolerance of UV-B radiation varies with species, and the radiation could affect weed ecology and management. Variations In growth, photosynthesis and defense system among four important agronomic weeds, Abutllon theophrastl Medlk, Amaranthus retroflexus L., Digitaria sanguinalis （L.） Scop and Chloris virgata Swartz, under Increased UV-B radiation （ambient and increased radiation at 2.7, 5.4 and 10.8 kJ.m^-2.d-1） were studied In the greenhouse experiment. After 2 weeks of radiation, the shoots＇ dry mass decreased with increasing UV-B radiation except for D. sanguinalis. The reduction in biomass was the result of changes in morphology and physiology. Higher levels of UV-B treatment decreased the leaf area, plant height, net photosynthetic rate and chlorophyll contents, while it increased the contents of wax and UV-B absorbing compound in all species, except for A. retroflexus, which did not increase significantly. The activity of superoxide dismutase, catalase, ascorbate peroxide and the content of ascorblc acid changed differently among the weed species as UV-B radiation increased. D. sangulnalls was the most tolerant and A. retroflexus the most sensitive to increased UV-B radiation. The results also show that the two grass species （D. sanguinalis and C. virgata） were more tolerant to UV-B radiation than the two broadleafed species （A. theophrasti and A. retroflexus）. The UV-B absorbing compound and leaf wax played Important roles against UV-B damages in the two grass weeds. The overall results suggest that weed community, competition and management will be altered by continuous ozone depletion.

Physiological Defense Mechanism of Ligularia intermedia Against UV-B Radiation on Dongling Mountain

Ligularia intermedia growing at different altitudes were used to investigate the mechanism of ultraviolet (UV) resistance on physiological aspects in the field. The tests compared the absorbance of the UV absorbing compound, the content of chlorophyll a, chlorophyll b, and carotenoids, and the activities of peroxidase (POX) and superoxide dismutase (SOD) in Ligularia intermedia growing at three different altitudes on Dongling Mountain in northern China. There were no significant differences between the plants growing at 1160 m and 1820 m. However, all of these factors increased dramatically at 2190 m. The results indicate that the UV resistance of the plants mainly depends on the mechanism of filtering the radiation and preventing the reactive oxygen species (ROS) damage produced by UV B