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The uniformity, coating thickness and adhesion of uranium(235U) plating on fission ionization chamber electrode are the key factors affecting the sensitivity of neutron detector. In this paper, ethanol is used as electroplating solution and platinum wire as anode. By investigating the effects of cathode plating process(aluminum tube), pH value, current density, initial U（Ⅵ） concentration in plating solution and electroplating time on electroplating efficiency and coating, the optimum process parameters of uranium electroplating were determined. The results show that when the current density is 6.50 mA/cm2, the electroplating time is 30 min, pH=2.6, the electrode spacing is 12 mm and the initial U（Ⅵ） mass concentration in the plating solution is 196 mg/mL, the electroplating efficiency can reach about 92.4% and the coating thickness can reach 2.26 mg/cm2. The coating was characterized by X-ray photoelectron spectroscopy(XPS) and scanning electron microscopy(SEM-EDS). XPS shows that U exists in the form of hexavalent U polymer and tetravalent uranium dioxide(UO2) with high purity. SEM shows that the surface of the coating is flat, dense and firmly bonded with the substrate. The scratch test results show that the adhesion of the U coating is weak.

Indium droplets were grown on GaAs (001) substrates by droplet epitaxy method. The samples grown at different temperatures were characterized by atomic force microscope (AFM), and the surface morphology was observed. The study illustrates that indium droplets are very sensitive to the substrate temperature. The droplet density decreases with the increase of the substrate temperature, and its size increases with the increase of the substrate temperature. The physical mechanism of indium droplet formation at different substrate temperatures was analyzed, and the reason was explained. According to the relationship between the maximal cluster density and substrate temperature in nucleation theory, the functional relationship between the density of indium droplets and the substrate temperature is calculated as nx =5.17 exp(0.69 eV/kT). [ABSTRACT FROM AUTHOR]

To investigate the ripening behavior of Al droplets on GaAs surface, Al droplets were prepared onto GaAs substrates by droplet epitaxy. The growth and nucleation of Al droplets were effectively controlled by controlling the annealing time without arsenic pressure. By combining thermodynamic principles and crystal growth theories, physical explanation of the different sample morphology and constructed the basic models about ripening, etching and diffusion behaviors during the process of droplets morphology transition were carried out. The calculation results confirm that the droplet will be consumed by etching and diffusion process simultaneously when the ripening behavior reaches the equilibrium state after annealing of 239 s. [ABSTRACT FROM AUTHOR]

International diversification is a main way to realize the preservation and appreciation of foreign exchange reserves and offshore investment funds. This paper investigates the benefits of international diversification based on the selection of investment markets and application of investment strategies from the perspective of Chinese investors. Our results show that, compared with diversifying into developed markets, diversifying into emerging markets helps Chinese investors gain a higher return, which will be helpful for the preservation and appreciation of foreign exchange reserves and offshore investment funds. If investors decide to invest in developed markets, the strategy of minimizing tracking error variance can also enable investors to achieve the target. On the other hand, if developed and emerging markets are all included in target markets, then the equally weighted investment strategy could bring investors the best performance. [ABSTRACT FROM AUTHOR]

A series of phthalazine ketone compounds were synthesized and the structures were confirmed by H NMR and HR-MS spectrum. All target compounds were obtained through 7 steps, including selective reduction, nitration, bromination, ring enlargement, reduction, Knoevenagel and acylated reaction. The compounds were evaluated for their immunosuppressive effects of T-cell proliferation and inhibitory activity of IMPDH type II in vitro, as well as their structure-activity relationship were assessed. Several compounds exhibited strong immunosuppressive properties, especially compounds 7f and 7h, with IC50 values of 0.093 micromol x L(-1) and 0.14 micromol x L(-1) respectively, which were superior to mycophenolic acid. The information obtained from the studies may be useful for further research on the immunosuppressive agents.

Objective: To summarize the clinical experience of extracorporeal membrane oxygenation (ECMO) treatment for adult refractory cardiogenic shock., Methods: From January 2003 to January 2011, patients with refractory cardiogenic shock required veno-arterial ECMO by failure of conventional therapy and intra-aortic balloon pump counterpulsation therapy were retrospectively studied. Patients with severe traumatic brain injury, advanced malignancies and multiple organ failure were excluded. Patients were divided into weaned group (n = 31) and not weaned group (n = 23) according to the ECMO weaning., Results: The duration of ECMO was 24.16 (14.12, 56.75) hours. Twenty-two out of 31 patients in the weaned group survived and were discharged, 9 patients died after successfully weaned from ECMO (5 due to multisystem organ failure, 2 due to reoccurred cardiogenic shock, 1 due to infectious shock and 1 due to disseminated or diffuse intravascular coagulation). Pre-ECMO mean arterial pressure, ejection fraction, the duration of ECMO were significantly higher while pre-ECMO blood lactate [(8.64 ± 3.17) vs. (14.44 ± 2.52) , P < 0.01], the duration of ROSC [ (16.70 ± 5.29) vs. (35.64 ± 5.89), P < 0.01] and multisystem organ failure [0 vs. 17.4% (4/23) , P < 0.05] were lower in weaned group than in not wean group., Conclusions: ECMO is an effective mechanical assistant therapy strategy for adult refractory cardiogenic shock patients. Timely applying this strategy on suitable patients is crucial for the success of ECMO. Cardiac function and reversibility of heart failure are key factors determine the fate of weaned or not weaned ECMO in adult refractory cardiogenic shock patients.

Background: Cervical spondylotic radiculopathy is a commonly encountered and frequently occurring disease. Traditional Chinese osteopathic manipulations may have better therapeutic efficacy than that of other methods in treating patients with cervical spondylotic radiculopathy., Objective: To evaluate the clinical therapeutic effects of cervical fixed-point traction manipulation in treating patients with cervical spondylotic radiculopathy., Design, Setting, Participants and Interventions: A prospective, randomized controlled trial was adopted. Eighty-four patients with cervical spondylotic radiculopathy were randomly divided into treatment group (n=42) and control group (n=42). All patients were enrolled from the outpatient service of Department of Rehabilitation of Chinese PLA General Hospital of China. Patients received oral and written information about clinical procedures before giving their written informed consent. The patients were treated with cervical fixed-point traction manipulation (treatment group) or cervical computer traction (control group). Cervical fixed-point traction was performed once every other day for a total of seven treatment periods and cervical computer traction was performed 30 min, once per day for 14 d., Main Outcome Measures: Before and after treatment, visual analogue scale (VAS) score and temperature of upper limb skin (normal limb and abnormal limb) detected by infrared thermal imaging system were contrastively analyzed., Results: Five patients were lost to follow-up, one patient in the treatment group and four patients in the control group. There were significant differences in VAS score and temperature difference between the normal and abnormal upper limbs of infrared thermal imaging in the treatment group (t=28.652, P<0.01; t=64.214, P<0.01) or in the control group (t=14.484, P<0.05; t=84.425, P<0.05) compared between before and after treatment. After treatment, the changes in VAS score and temperature difference of normal and abnormal upper limbs in the treatment group were more obvious compared with the control group (t=7.494, P<0.01; t=5.321, P<0.01)., Conclusion: Cervical fixed-point traction manipulation has better efficacy than cervical computer traction in treating patients with cervical spondylotic radiculopathy.

Objective: To study the chemical constituents of Choerospondias axillaries., Methods: All compounds were isolated and purified by normal column chromatograph, paper thin layer chromatograph and sephadex chromatograph, the chemical strucures were mainly elucidated by ESI-MS and NMR spectra., Results: seven compouds were isolated from the Choerospondias axillaries and as following: beta-sitostero (I), hexadecanoic acid (II), correctitude fourty-two alkyl acid (III), daucosterol (IV), quercetin (V), rutinum (VI), lueolin-3'-O-beta-D-glucopyranoside (VII)., Conclusion: Compounds II, III, V, VII are isolated from this plant for the first time.

Applying supercritical CO2 fluid extraction technology, flavonoids were extracted from Chinese traditional medicine asarum heterotropoides, atractylodes macrocephala, and rheum palmatun. Using the method of autoxidation pyrogallol (known as 325 nm method), the superoxide radical scavenging effect of the extraction was carried out in the buffer solution of HCl-tris (pH 8.2). With spectrophotometry, hydroxyl radical created by the system Co2+ + H2O2 in the reaction like Fenton reaction was eliminated by alizarin violet as the color developing agent in the buffer solution HCl-tris (pH 9.0) and the reaction condition was investigated. Result showed that these extractions are elimination agent for these radicals. Asarum heterotropoides is the best of the three.

The interaction between polymyxin B sulfate and ct-DNA was studied with ethidium bromide (EB) probe by UV spectroscopy, fluorescence spectroscopy, fluorescent polarization etc. The phenomena of hyperchromism effect and fluorescence quenching proved that polymyxin B sulfate in buffer solution at pH 7.4 can intercalate into the base pairs of ct-DNA. This interaction can cause conformational change of ct-DNA double helix. This interaction can be inhibited in the presence of high concentration of ions. At the same time, PB can combine with the phosphate group of ct-DNA by non-characteristic static force. In this paper, the interaction of PB and ct-DNA was made further discussion.