Axial Local Lifetime Control in High-Voltage Diodes Based on Proximity Gettering of Platinum by Proton-Implantation Damages

A new lifetime control technique-localized platinum lifetime control （LPLC） is introduced. Silicon samples are implanted with 550keV protons at dosages from 1 × 10^13 to 5 × 10^14 cm^-2. Subsequently, platinum diffusion in silicon is performed at 700 or 750℃ for 15 or 30min,respectively. Then the in-diffused platinum into damaged regions of the proton-implanted silicon is investigated by use of deep-level transient spectroscopy （DLTS）. Finally, for all of the LPLC samples, the distribution of the in-diffused substitutional platinum agrees well with the damage distribution resulting from the low-dosage proton implantation. Also, the diodes show a very low leakage current even at elevated temperatures while keeping the major advantages of ion irradiation devices, including low turn-off loss and soft recovery.

The Chlorophyll Biosynthesis in Lotus Embryo Is Light-dependent

Angiosperms need light to synthesize chlorophyll, but lotus (Nelumbo nucifera Gaertn.) embryo was suspected to have the ability to form chlorophyll in the dark because lotus embryo can turn into green under the coverage of four layers of integuments (cotyledon, seed coat, pericarp, lotus pod) which were thought impossible for light to pass through. The authors excluded this possibility based on two experimental results: First, enclosing the young lotus pod with aluminium foil, the growth of louts embryo continued, but the chlorophyll formation was seriously inhibited. A lot of protochlorophyllide, chlorophyll precursor, were accumulated, most of which were combined with LPOR (light dependent protochlorophyllide oxidoreductase). Second, DPOR (dark or light-independent protochlorophyllide oxidoreductase) was the enzyme necessary for chlorophyll synthesis in the dark. The genes encoding DPOR were conservative in many species, but no homologues could be found in lotus genome. Taken together, authers' results clearly demonstrated that lotus embryo synthesizes chlorophyll only through the light-dependent pathway.

Bifunctional TiO2 Catalysts for Efficient Cr（VI） Photoreduction Under Solar Light Irradiation Without Addition of Acids

Bifunctional TiO2 photocatalysts co-doped with nitrogen and sulfur were prepared by the controlled thermal decomposition of ammonium titanyl sulfate precursor. They have both photocatalytic activity and Brφnsted acidity, and thus are active in the photoreduction of Cr（VI） under solar light irradiation without the addition of acids. The activity is superior to that of Degussa P25 in the acidified suspension at the same pH adjusted by H2SO4.

Antiviral therapy for hepatitis B virus-related hepatocellular carcinoma after radical hepatectomy

Objective： To assess the effect of antiviral therapy for hepatitis B virus （HBV）-related hepatocellular carcinoma （HCC） after radical hepatectomy. Methods： A total of 478 HBV-related HCC patients treated by radical hepatectomy were retrospectively collected. Patients in the treatment group （n=141） received postoperative lamivudine treatment （100 rag/d）, whereas patients in the control group （n=337） did not. Recurrence-free survival （RFS） rates, overall survival （OS） rates, treatments for recurrent HCC and cause of death were compared between the two groups. Propensity score matching （PSM） analysis was also conducted to reduce confounding bias between the two groups. Results： The 1-, 3-, and 5-year RFS rates didn＇t significantly differ between the two groups （P=0.778）; however, the 1-, 3-, and 5-year OS rates in the treatment group were significantly higher than those in the control group （P=0.002）. Similar results were observed in the matched data. Subgroup analysis showed that antiviral treatment conferred a significant survival benefit for Barcelona Clinical Liver Cancer stage A/B patients. Following HCC recurrence, more people in the treatment group were able to choose curative treatments than those in the control group （P=0.031）. For cause of death, fewer people in the treatment group died of liver failure than those in the control group （P=0.041）. Conclusion： Postoperative antiviral therapy increases chances of receiving curative treatments for recurrent HCC and prevents death because of liver failure, thereby significantly prolonging OS, especially in early- or intermedian-stage tumors.

Tracking charge transfer pathways in SrTiO_(3)/CoP/Mo_(2)C nanofibers for enhanced photocatalytic solar fuel production

Photocatalytic solar fuel generation is currently a hot topic because of its potential for solving the energy crisis owing to its low cost and zero-carbon emissions.However,the rapid bulk recombination of photoexcited carrier pairs is a fundamental disadvantage.To resolve this problem,we synthesized a dual cocatalysts system of cobalt phosphide(Co P)and molybdenum carbide(Mo_(2)C)embedded on strontium titanate(Sr TiO_(3))nanofibers.Compared with those of pristine SrTiO_(3) and binary samples,the dual cocatalysts system(denoted SCM)showed a significant improvement in the hydrogen evolution and CO_(2) reduction performance.Further,the structure of SCM effectively promoted spatial charge separation and enhanced the photocatalytic performance.In addition,the Schottky junction formed between the SrTiO_(3) and cocatalysts enabled the rapid transfer of photoexcited electrons from SrTiO_(3) to the cocatalysts,resulting in effective separation and prolonged photoexcited electron lifetimes.The electron migration route between SrTiO_(3) and the cocatalysts was determined by in situ irradiation X-ray spectroscopy,and band structures of Sr TiO_(3) and the cocatalysts are proposed based on results obtained from UV-vis diffraction reflection spectroscopy and ultraviolet photoelectron spectroscopy measurements.On the basis of our results,the dual cocatalysts unambiguously boosts charge separation and enhances photocatalytic performance.In summary,we have investigated the flux of photoexcited electrons in a dual cocatalysts system and provided a theoretical basis and ideas for subsequent research.

UV-TiO_2 photocatalytic disinfection and photoreactivation of pathogenic bacterium in municipal wastewater

The disinfected bacteria will be a photoreactivation under the irradiation of the sunlight,and the light intensity plays an important role in the bacteria resurrection.The effect of light intensity on photoreactivation of Escherichia coli(E.coli) and Enterococcus faecalis(E.faecalis) in secondary effluents which were disinfected respectively by pure UV and UV-TiO_2 was investigated.The results show that the disinfection efficiency of UV-TiO_2 is much higher than that of the pure UV disinfection.The photoreactivation rate of E.coli is much higher in pure UV disinfection than in UV-TiO_2 photocatalytic disinfection.Under high light intensity in UV-TiO_2 disinfection,high resurrection rate can be induced.However,a higher resurrection rate can be introduced even under low light intensity in pure UV disinfection alone.Meanwhile,UV-TiO_2 disinfection has a strong inhibition effect on E.faecalis photoreactivation.When the light intensity is lower than 21 μW/cm^2,nearly no resurrection of E.faecalis occurs after 72 h resurrection irradiation,and a little resurrection rate is observed only under a strong photoreactivating light intensity.

Surface Modification of Cu-Cr Complex by NIR and MIR Laser

Irradiated by infrared laser, the surface reducibility and adsorbability of Cu-Cr complex could be improved, owing to the interaction of photo-fragmentation and laser texturing. Analyzed by the binding energy spectra and the auger spectra, the valence states of chromium ion and copper ion were+3 and+1 after radiation respectively, which still had the reducibility to release electrons. In contrast with the near-infrared(NIR)1 064 nm and mid-infrared(MIR) 10 600 nm laser at the same average output power of 15 W, the reduced metal percentage in the Cu-Cr complex was obviously distinguished at the depth from nanometer to micron. After chemical plating, the average coating thickness and mean-square deviation of the NIR sample were 11.61 μm and 0.30 for copper layer, and 2.69 μm and 0.08 for nickel layer. The results were much better than those of the MIR sample.

Agriculture Development-induced Surface Albedo Changes and Climatic Implications Across Northeastern China

To improve the understandings on regional climatic effects of past human-induced land cover changes,the surface albedo changes caused by conversions from natural vegetation to cropland were estimated across northeastern China over the last 300 years,and its climatic effects were simulated by using the Weather Research and Forecasting (WRF) model.Essential natural vegetation records compiled from historical documents and regional optimal surface albedo dataset were used.The results show that the surface albedo decreased by 0.01-0.03 due to conversions from grassland to cropland in the Northeast China Plain and it increased by 0.005-0.015 due to conversions from forests to cropland in the surrounding mountains.As a consequence,in the Northeast China Plain,the surface net radiation increased by 4-8 W/m 2,2-5 W/m 2,and 1-3 W/m 2,and the climate was therefore warmed by 0.1℃-0.2℃、0.1℃-0.2℃、 0.1℃-0.3 ℃ in the spring,autumn and winter,respectively.In the surrounding mountain area,the net radiation decreased by less than 1.5 W/m 2,and the climate was therefore cooled too slight to be detected.In summer,effects of surface albedo changes on climate were closely associated with moisture dynamics,such as evapotranspiration and cloud,instead of being merely determined by surface radiation budget.The simulated summer climatic effects have large uncertainties.These findings demonstrate that surface albedo changes resulted in warming climate effects in the non-rainy seasons in Northeast China Plain through surface radiation processes while the climatic effects in summer could hardly be concluded so far.

Morphology and survival of cryopreserved-thawed ovarian tissues after heterotopic autotransplantation

Objective： The aim of our study was to observe the survival and morphological changes of thawed ovarian tis- sues after heterotopic transplantation. Methods： Twenty SPF-SD female rats （5-6 weeks old） were equally randomized into the control group and experimental group. In control group, the freshly isolated ovaries were fixed in formalin. In experimental group, the freshly isolated ovaries were vitrified immediately and cut into thin slices. After stored in liquid nitrogen for 21 days, the tissues of experimental group were rapidly thawed and transplanted into back muscles of rats for 2 or 4 weeks, respectively. After that, all rats in experimental group were sacrificed and the ovarian tissues were collected and fixed in 4% formaldehyde solution. Then the ovarian tissues were stained with HE and observed under the light confocal microscope. Re- suits： With the naked eyes, there was no specific alteration except the size reduction with color changing. Under microscopy, we found normal cortex and medulla in the ovary, and the primordial follicles and follicles in various stages were observed in the cortex. The normal oocytes in ovarian tissues of experimental group were significant decreased than in the control group. Conclusion： The ovarian tissues survive well in experimental group and there is no significant difference in the proportion of follicles between different times （2 and 4 weeks） after grafting. Our results suggest that thawed ovarian tissues could survive after heterotopic transplantation into back muscles of rat models and maintain their morphology and function.

Irradiation Damage of Nano-C2S Particles Studied by In-Situ Transmission Electron Microscopy

Development of a reactive nanocement is a new approach to improve the physical and chemical properties of construction materials. However, due to the decreased size of cement particles, beam damage during transmission electron microscope （TEM） observation becomes more severe than in conventional cement. In this work, irradiation damage to nano-C2S （dicalcium silicate） is observed and studied by in-situ evolution of diffraction patterns （DP）, high resolution TEM （HRTEM）, and electron energy-loss spectroscopy （EELS）. The results show that the damage to nano-C2S occurs through a decomposition reaction. Nano-C2S is first amorphized, and then re-crystallized into CaO nano-crystals with average size of 7 nm surrounded by an amorphous matrix of Si and SiO2. During this process, C2S particles exhibit volume shrinkage. The damage energy causing the reaction was analyzed and electron-electron inelastic scattering produced radiolysis and heat, leading to the observed phenomena.

Glacier Changes during the Past 40 Years in the West Kunlun Shan

Recent studies on glaciers in the West Kunlun Shan, northwest Tibetan Plateau, have shown that they may be stable or retreating slightly. Here, we assess changes in the mass of the glaciers in the West Kunlun Shan(WKS) in an attempt to understand the processes that control their behavior. Glaciers over the recent 40 years(1970-2010) have shrunk 3.4±3.1%in area, based on a comparison between two Chinese glacier inventories. Variations of surface elevations, derived from ICESat-GLAS(Ice, Cloud, and Land Elevation Satellite-Geoscience Laser Altimeter System) elevation products(GLA14 data) using the robust linear-fit method, indicate that the glaciers have been gaining mass at a rate of 0.23±0.24 m w.e./a since 2003. The annual mass budget for the whole WKS range from 2003 to 2009 is estimated to be 0.71±0.62 Gt/a. This gain trend is confirmed by MOD10A1 albedo for the WKS region which shows a descent of the mean snowline altitude from 2003 to 2009.

Photo Socialization in Digital Natives

In the following work of research, we shall present the results of a study on forms of digital photographic socialization as carried out by the so-called ＂digital natives＂ in order to explore their competence in managing digital photographic output and cultural practices. This shall be done under the following categories of analysis： snapshot, organization, socialization, reception, privacy, and copyrights in digital photography. The study explores the forms of digital photography production, technical problems of photographic management and the final uses that digital photographers give to their photos in terms of web tools 2.0, mobile telephones and social networks. Digital photography technology, compact cameras, mobile phones with cameras, specialized websites in photography and the lnternet generate new forms of production and emerging styles of digital photographic socialization. The study is carried out using a defined sample of university students, those digital natives who create and use digital photography.

从两张照片引起的回忆

1986年冬,我在整理东西时,无意中找到了我已努力寻找达十余年之久的两张珍贵照片,这两张照片都是先父蒋抑卮和鲁迅先生于本世纪初在日本合影的原照。当1976年,国家徵集有关鲁迅先生的书信、照片等文物时。

朱吉人与朱安及鲁迅

在朱安逝世40周年的日子里,上海鲁迅纪念馆收到朱吉人先生捐赠的一帧朱安晚年的照片。这帧照片,是朱安在1941年阴历11月19日(即公历1942年1月5日)摄于北京西三条寓院内,是一帧较全面反映朱安晚年风貌的照片,原照规格为8.8×6.6厘米,照片背面留存着'阴历十一月十九日六十三岁时一九四一'的钢笔字样,不知为何人手书。这帧照片是朱安赠其内侄朱吉人的纪念物,它是朱安与朱吉人姑侄友情的象征。

旧照堪珍贵 难忘赵景深

年初在整理旧信札时,发现一只未写信址的旧信封,抽出信瓤一看,原来是一张旧照片。这张照片不是原照,而是从报上剪下来的,粘贴在一张有横线的纸片上。照片已经泛黄,可见存放很久了。看到这张剪照,不禁勾起我对30年前一段往事的回忆,脑海里立即浮现出著名文学家、戏曲家、复旦大学中文系教授赵景深先生熟悉的面容,使我陷入深深的追思。

Short-working-distance optical imaging system and method for surface detection of underwater structures

In the surface imaging of underwater structures, long working distance will reduce image quality due to the turbidity of water. To acquire high definition and large field of view(FOV) images for surface detection, a short-working-distance underwater imaging system is proposed based on camera array. A multi-view calibration and rectification method is developed. A look-up table(LUT) method and a multi-resolution spline(MRS) method are applied to stitch array images real-time and seamlessly.Experiments both in the air and in the water are conducted. Strength and weakness of the LUT and MRS methods are discussed.Based on the results, the effectiveness in surface detection of underwater structures is verified.

Systematic review and meta analysis of randomized controlled trials on Tianmagouteng decoction in treatment of primary hypertension with liverYang hyperactivity syndrome

OBJECTIVE： To assess the efficacy of Tianma- gouteng decoction in the treatment of primary hypertension with liver yang hyperactivity syndrome. METHODS： The databases of MEDLINE （1950- 2012）, EMbase （1980-2012）, China biology medicine （CBM） （1994-2012）, China national knowledge infrastructure （CNKI） （1989-2012）, Weipu （VIP） （1995-2012） and Wanfang （1989-2012） were searched and we performed manual searches for conference proceedings to select randomized controlled trials （RCTs） on Tianmagouteng decoction for the treatment of primary hypertension with liver Yang hyperactivity syndrome. Studies were en- rolled according to the study-selecting criteria. The methodological quality was evaluated, data were extracted and meta-analyses were conducted with RevMan 4.2 software. RESULTS： Nine RCTs were selected involving 784 patients with no significant difference in decrease in systolic blood pressure （SBP）[0R=1.02, 9.5% CI （-0.24, 2.29）, P=0.10] and diastolic blood pressure（DBP） [OR=0.56, 95% CI （-0.10,1.23）, P=0.11] between the Tianmagouteng group and the control group. While there was a significantly larger increase in serum superoxide dismutase （SOD）[OR= 6.26, 95% CI （1.27,11.66）, P=0. 01] in the Tianmagouteng group than that in the control group CONCLUSION： Tianmagouteng decoction can decrease both systolic and diastolic blood pressure and greatly increase serum SOD. Due to poor quality of included studies, the efficacy needs to be further assessed.

Anelasticity of twinned CuO nanowires

The mechanical behavior of CuO nanowires （NWs） was investigated by in situ transmission electron microscopy. During compression, the NWs exhibited high bending capabilities associated with high mechanical stress. Interestingly, anelasticity was consistently observed after stress release. Further investigations indicate that the anelasticity is intrinsic to the CuO NWs, although electron- beam irradiation was proved capable of accelerating the shape recovery. A mechanism based on the cooperative motion of twin-associated atoms is proposed to account for this phenomenon. The results provide insight into the mechanical properties of CuO NWs, which are promising materials for nanoscale damping systems.

Statistic of a Gaussian beam from an arbitrary rough target in the single passage atmospheric turbulence

The extended Huygens-Fresnel principle and Goodman model was utilized for target surface to derive the mutual coherence function(MCF) of a Gaussian beam reflected from an arbitrary rough target in atmospheric turbulence. According to the MCF, expressions of the mean irradiance and average speckle size at the receiver were obtained. The analysis indicated that the mean intensity is closely related to the ratio of root mean square(rms) height to the lateral correlation length. In addition, the speckle size at the receiver is associated with turbulence strength, propagation distance and roughness of the target. The results can be reduced to the result of a Gaussian beam illuminating rough target and scattering from a target in free space.

Impact of Grazing Exclusion on the Surface Heat Balance in North Tibet

The grazing exclusion program used by the Tibetan government to protect the ecological environment has changed the vegetation and impacted the surface heat balance in North Tibet. However, little information is available to describe the in?uences of the current grazing exclusion program on local surface heat balance. This study uses the records of fenced grassland patch locations to identify the impact of grazing exclusion on surface heat balance in North Tibet. The records of fenced grassland patch locations, including the longitude, latitude, and elevation of the vertices of each fenced patch(polygon shapes), were provided by the agriculture and animal husbandry bureaus of the counties where the patches were located. ArcGIS 10.2 was used to create polygon shapes based on patch location records. Based on satellite data and the surface heat balance system determined by the model, values for changes in land surface temperature(LST), albedo and evapotranspiration(ET) induced by grazing exclusion were obtained. All of these can influence surface heat balance and alter the fluctuation of LST in the northern Tibetan Plateau. The LST trends for day and night showed an asymmetric diurnal variation, with a larger magnitude of warming in the day than cooling at night. The maximum decrease in absorbed shortwave of LST(?0.5 ? ?0.4 ℃ per decade) occurred in the central region, while the minimum decrease(?0.2 ? ?0.1 ℃ per decade) occurred in the eastern region. The decreased latent heat lead to the LST increased maximum(>1 ℃ per decade) occurred in the central region, The eastern region increased at a rate of 0.2?0.5 ℃ per decade, while the minimum increase(0?0.1 ℃ per decade) occurred in the northwestern region.