Gel-state polybenzimidazole proton exchange membranes with flexible alkyl sulfonic acid side chains for a wider operating temperature range(25–240 ℃)

High-temperature proton exchange membrane fuel cells(HT-PEMFC) possess distinct technical advantages of high output power, simplified water/heat management, increased tolerance to fuel impurities and diverse fuel sources, within the temperature range of 120–200 ℃. However, for practical automobile applications, it was crucial to broaden their low-temperature operating window and enable cold start-up capability. Herein, gel-state phosphoric acid(PA) doped sulfonated polybenzimidazole(PBI) proton exchange membranes(PEMs) were designed and synthesized via PPA sol-gel process and in-situ sultone ring-opening reactions with various proton transport pathways based on absorbed PA, flexible alkyl chain connected sulfonic acid groups and imidazole sites. The effects of flexible alkyl sulfonic acid side chain length and content on PA doping level, proton conductivity, and membrane stability under different temperature and relative humidity(RH) were thoroughly investigated. The prepared gel-state membranes contained a self-assembled lamellar and porous structure that facilitated the absorption of a large amount of PA with rapid proton transporting mechanisms. At room temperature, the optimized membrane exhibited a proton conductivity of 0.069 S cm^(-1), which was further increased to 0.162 and 0.358 S cm^(-1)at 80 and 200 ℃, respectively, without additional humidification. The most significant contribution of this work was demonstrating the feasibility of gel-state sulfonated PBI membranes in expanding HT-PEMFC application opportunities over a wider operating range of 25 to 240 ℃.

Profiling and geographical distribution of seed oil content of sunflower in Ukraine

The sunflower has the potential to be a highly competitive crop owing to its diversity market and the valuable oil it produces.Nevertheless,the amount of sunflower seed oil-a key factor for the crushing industry-is affected by genotype and environment,which sometimes is difficult to predict.The paper analyzes the theoretical principles of sunflower growth in Ukraine,highlights the current trends in the sowing of this crop,the influence of climatic factors of the environment on the prospects of the oilseed sunflower yield.The results of the research are presented for 3 years(2014-2016),during the authors conducted a grain quality observatory at the regional level,taking into account the climatic conditions of sunflower growth in different natural zones of Ukraine(from 45
to 51
north latitude and from 22
to 37
east longitude).Additionally,the research includes the coefficient of significance of the deviation from long-term climatic indicators,which makes it possible to forecast sunflower yield in the future.The analyzed data was obtained from the commercial fields with a minimum area of 40 ha in all Ukrainian regions except Crimea peninsula,Donetsk and Luhansk regions.The results obtained in research show the great diversity of oil content index as per both latitude and longitude meaning.If we consider the entire country,this survey shows that the seed oil content can change dramatically from year to year:e.g.47.5%in one year versus 45.7%in another year.Regionally,these changes have a completely different dynamic with a gradual decrease in seed oil content in the southern part of the country.The main goal of the research was to identify the best sunflower growing areas in Ukraine according to the oil content index.

Fuzzy Optimum Model of Semi-Structural Decision for Lectotype Optimization of Offshore Platforms

In the process of concept design of offshore platforms, it is necessary to select the best from feasible alternatives through comparison and filter. The criterion set, used to evaluate and select the satisfying alternative, consists of many qualitative and quantitative factors. Therefore, the selection is a problem of multicriteria and semi-structural decision-making. Different from traditional methods in semi-structural decision-making, a new framework and methodology is presented in this paper for evaluation of offshore platform alternatives, First, the criterion set is established for the evaluation of alternatives. Next, the approach is studied to construct the relative membership degree matrix, in which both qualitative and quantitative factors are consistent with the uniform calculating standard. And then a new weight-assessing method is developed for calculation of the weights based on the relative membership degree matrix. Finally, a multi-hierarchy fuzzy optimum model is adopted to select the satisfying offshore platform alternative. A case study shows that the new framework and methodology are scientific, reasonable and easy to use in practice.

Anti-fatigue effects of salidroside in mice

目的将在老鼠学习 salidroside 的反疲劳效果。完全， 120 个正常男 Kunming 鼠标基于身体重量被使随机化进 5 个组(4 个 salidroside 干预组和控制组) 的方法。控制组被给提取的水和组们被给 salidroside 的各种各样的剂量的 4 干预(60， 180， 360， 720 mg/kg ) 为 15 连续的天分别地。层次喂奶，浆液脲氮，肌肉和肝肝糖，最长的游泳时间和血红素在游泳前后被决定测试。结果 salidroside 的不同剂量显著地变长游泳时间并且当减少的时，增加了血红素和肌肉和肝肝糖的内容与控制组相比显著地在血喂奶，特别在 180 mg/kg salidroside 组。结论 Salidroside 在老鼠上有显著反疲劳效果。这些效果是剂量依赖者，并且大多数 biomarkers 上的最强壮的效果与中间的剂量被看见。

Distribution and their pollution assessment of heavy metals in the sediments of the Yalu River Estuary and its adjacent coastal waters

The present paper deals with the distribution patterns of heavy metals and the associated influenc- ing factors in the Yalu River Estuary and its adjacent coastal waters. Based upon the analysis of the surficial and core sediments measurements, the pollution of heavy metal and potentiM ecological risk were evaluated. The burial flux and contents of heavy metals （except for copper） have been continuously increasing since the 1920s. Therefore, the gross potential ecological risk for the sedi- ments was high or very high, and the study area was endangered by heavy metals contamination. Heavy metals originated mainly from upstream pollutant input, correlation analysis showed that chromium, nickel, zinc~ cadmium, lead, arsenic, and mercury in the sediments of the middle and west channels as well as the sea area of the western Yalu River Estuary concentrations were most probably derived from similar sources. In contrast, the metal of copper most probably originated from sources different from the other metals. Preliminary studies indicate that copper contamina- tion was most likely the result of emission from mining activities situated at the upstream of the river. The contents of heavy metals in the sediments of estuarine turbidity maximum zone of Yalu River were larger than those of any other areas in the middle channel. With large portion of fine sediments, weaker hydrodynamics, and richer sources of heavy metals, the sediments of the west channel, were even more enriched with heavy metals than those of the middle channel.

Western Indian Ocean SST signal and anomalous Antarctic sea-ice concentration variation

Teleconnection between El Nino/La Nina-Southern Oscillation （ENSO） phenomenon and anomalous Antarctic sea-ice variation has been studied extensively.In this study,impacts of sea surface temperature in the Indian Ocean on Antarctic sea-ice change were investigated during Janaury 1979 and October 2009.Based on previous research results,sea areas in the western Indian Ocean （WIO;50°–70°E,10 °–20 °S） are selected for the resreach.All variables showed 1-10 year interannual timescales by Fast Founer Tranaform （FFT） transformation.Results show that i） strong WIO signals emerged in the anomalous changes of Antarctic sea-ice concentration;ii） significant positive correlations occurred around the Antarctic Peninsula,Ross Sea and its northwest peripheral sea region iii） negative correlation occurred in the Indian Ocean section of the Southern Ocean,Amundsen Seas,and the sea area over northern Ross Sea;and iv） the atmospheric anomalies associated with the WIO including wind,meridional heat flux,and surface air temperature over southern high latitudes were the possible factors for the teleconnection.

Substance P enhances the proliferation of rat anteriorpituitary cells in vitro

The undecapeptide substance P(SP) was shown to be intimately involved in both the structural and functional aspects of the anterior pituitary. Yet, in addition to its influences on hormonal secretion, SP may well possess more actions in this master gland. The present study was ftherefore aimed to investigate the effect of SP on the proliferation of rat anterior pituitary cells in primary culture. It was found that SP could dose-dependently increase the ineorporation of tritiated thymidine (3H-TdR)into cultured anterior pituitary cells. Other mammalian tachykinins such as neurokinin A and neurokinin B had similar effect but to varying degrees. The equipotent analogue of SP, Norleucine(11) -SP(Nle(11)-SP), also acted likewise, with its action antagonizable by spantide, a SP receptor blocker. To further characterize the nature of cells responsive to the challenge of SP, immunocytochemical staining against S-100 protein and some adenohypophyseal hormones was performed alone or plus autoradiography The results showed that the percentage of S-100 proteinimmunoreactive cells was apparently elevated by the addtion of Nle(11)-SP for 48 h, which indicates a preferential proliferation of folliculo-stellate cells under the regime. This was confirmed by increases in immunocytochemical or autoradiographical labelling indices of anterior pituitary cells treated similarly. Taken togethbr, these results reveal that the trophic action of SP observed previously in other tissues is also present at least in cultured rat anterior pituitary cells, with responding cells being predominantly folliculo-stellate cells as typified by S-100 proteinimmunoreactivity. Therefore, an intra-pituitary trophic action of SP in vivo could be anticipated.

A IP_N×IP_N Spectral Element Projection Method for the Unsteady Incompressible Navier-Stokes Equations

In this paper,we present a IP_N×IP_N spectral element method and a detailed comparison with existing methods for the unsteady incompressible Navier-Stokes equa- tions.The main purpose of this work consists of:(i) detailed comparison and discussion of some recent developments of the temporal discretizations in the frame of spectral el- ement approaches in space;(ii) construction of a stable IP_N×IP_N method together with a IP_N→IP_(N-2) post-filtering.The link of different methods will be clarified.The key feature of our method lies in that only one grid is needed for both velocity and pressure variables,which differs from most well-known solvers for the Navier-Stokes equations. Although not yet proven by rigorous theoretical analysis,the stability and accuracy of this one-grid spectral method are demonstrated by a series of numerical experiments.

Chromatin remodeling regulated by steroid and nuclearreceptors

Coactivators and corepressors regulate transcriptionby controlling interactions between sequence-specific transcription factors, the basal transcriptional machinery andthe chromatin environment. This review consider the access of nuclear and steroid receptors to chromatin, theiruse of corepressors and coactivators to modify chromatinstructure and the implications for transcriptional control.The assembly of specific nucleoprotein architectures andtargeted histone modification emerge as central controlling elements for gene expression.

Milestones in the Observations of Cosmic Magnetic Fields

Magnetic fields are observed everywhere in the universe. In this review, we concentrate on the observational aspects of the magnetic fields of Galactic and extragalactic objects. Readers can follow the milestones in the observations of cosmic magnetic fields obtained from the most important tracers of magnetic fields, namely, the star-light polarization, the Zeeman effect, the rotation measures (RMs, hereafter) of extragalactic radio sources, the pulsar RMs, radio polarization observations, as well as the newly implemented sub-mm and mm polarization capabilities. The magnetic field of the Galaxy was first discovered in 1949 by optical polarization observations. The local magnetic fields within one or two kpc have been well delineated by starlight polarization data. The polarization observations of diffuse Galactic radio background emission in 1962 confirmed unequivocally the existence of a Galactic magnetic field. The bulk of the present information about the magnetic fields in the Galaxy comes from analysis of rotation measures of extragalactic radio sources and pulsars, which can be used to construct the 3-D magnetic field structure in the Galactic halo and Galactic disk. Radio synchrotron spurs in the Galactic center show a poloidal field, and the polarization mapping of dust emission and Zeeman observation in the central molecular zone reveal a toroidal magnetic field parallel to the Galactic plane. For nearby galaxies, both optical polarization and multifrequency radio polarization data clearly show the large-scale magnetic field following the spiral arms or dust lanes. For more distant objects, radio polarization is the only approach available to show the magnetic fields in the jets or lobes of radio galaxies or quasars. Clusters of galaxies also contain widely distributed magnetic fields, which are reflected by radio halos or the RM distribution of background objects. The intergalactic space could have been magnetized by outflows or galactic superwinds even in the early universe. The Zeeman effect and polarization of sub-mm and mm emission can be used for the study of magnetic fields in some Galactic molecular clouds but it is observed only at high intensity. Both approaches together can clearly show the role that magnetic fields play in star formation and cloud structure, which in principle would be analogous to galaxy formation from protogalactic clouds. The origin of the cosmic magnetic fields is an active field of research. A primordial magnetic field has not been as yet directly detected, but itsexistence must be considered to give the seed field necessary for many amplification processes that have been developed. Possibly, the magnetic fields were generated in protogalactic plasma clouds by the dynamo process, and maintained again by the dynamo after galaxies were formed.

DC Arc Plasma Disposal of Printed Circuit Board

A new solid waste disposal technology setup with DC are plasma is presented. Being different from conventional combustion or burning such as incineration, it is based on a process called controlled high-temperature pyrolysis, the thermal destruction and recovery process. The results of vitrification of the circuit board is presented. The properties of vitrified product including hardness and leaching test results are presented. The final product (vitrified material) and air emission from the plasma treatment is environmentally acceptable.

Evaluation of Correction Algorithm for the Reflectance Measured with Optical Glass

The proposed algorithm for reflectance measured with optical glass has been verified with materials of various forms. The refiectances measured with optical glass (raw), without glass (true) and corrected by the algorithm are compared. The results show that the corrected reflectance agrees very well with true one and their color differences fall below the acceptable limit, which indicates the validity of the correction algorithm. The algorithm could be used not only for fiber-forming materials, but also for powder- forming, granulate-forming, etc.

Influences of vacancy defects on thermal conductivities of Ge thin films

The effects of vacancy defects on the thermal conductivity of Ge thin films were investigated by employing molecular dynamics （MD） simula- tions and theoretical analysis based on the Boltzmann equation. Both the MD and theoretical results show that the lattice thermal conductivity dramatically decreases with the increasing of vacancy concentration at 400 and 500 K. In addition, the dependence of vacancy concentration on the thermal conductivity of Ge thin films becomes less sensitive as the temperature increases. Theoretical results also confirm that the major part of the lattice thermal conductivity reduction is associated with the point-defect scattering and phonon-phonon scattering processes.

Eigen solutions of internal waves over subcritical topography

Diapycnal mixing plays an important role in the ocean circulation.Internal waves are a kind of bridge relating the diapycnal mixing to external sources of mechanical energy.Difficulty in obtaining eigen solutions of internal waves over curved topography is a limitation for further theoretical study on the generation problem and scattering process.In this study,a kind of transform method is put forward to derive the eigen solutions of internal waves over subcritical topography in twodimensional and linear framework.The transform converts the curved topography in physical space to flat bottom in transform space while the governing equation of internal waves is still hyperbolic if proper transform function is selected.Thus,one can obtain eigen solutions of internal waves in the transform space.Several examples of transform functions,which convert the linear slope,the convex slope,and the concave slope to flat bottom,and the corresponding eigen solutions are illustrated.A method,using a polynomial to approximate the transform function and least squares method to estimate the undetermined coefficients in the polynomial,is introduced to calculate the approximate expression of the transform function for the given subcritical topography.

Evaluation of stress concentration for planar tubular joints

In offshore tubular structures, a typical tubular joint may be subjected to three different types of basic loadings: axial, in-plane bending and out-of-plane bending, through its brace members. Each type will cause a different stress distribution at the joint intersection of structures. Moreover, the actual load condition of a tubular joint can be any combination of the above three basic load cases, for this reason, a combined loading was investigated in addition to these three basic loadings. This load is composed of an axial loading combined with a continuation of rotational bending loading obtained while rotate center of the brace around a circle. Different types of planar joints such as T, Y, X, K, DT, DY, DX, TY, TK, DTX, DTDY, and DTDK, with braces subjected to combined loading, were numerically analyzed to study the effect of those different cases of loading and different types of joints, on the stress concentration zone and values.

CASP8 promoter polymorphism,mRNA expression and risk of prostate cancer among Chinese men

Caspase-8 （CASPS） plays a key role in apoptosis. We examined by genotyping whether the -652 six-nucleotide insertion-deletion （6N ins/del） polymorphism in the CASP8 promoter region was associated with prostate cancer risk in a hospital-based case-control study of 406 Chinese prostate cancer patients and 408 age-matched cancerfree controls. Additionally, 23 prostate cancer tissues were analyzed for CASP8 mRNA expression. We found a significantly decreased prostate cancer risk for the 6N ins/del genotype [adjusted odds ratio （OR）=0.68; 95% confidence interval （C/）=0.51-0.92] and del/del genotype （OR=0.34; 95% CI=0.19-0.63） compared with the ins/ins genotype. The 6N del allele was associated dose-dependently with decreased prostate cancer risk （Ptrend = 0.001）. RT-PCR showed that individuals with the 6N del allele had lower CASP8 mRNA levels than those with the ins/ ins genotype （P = 0.024）. These findings suggested that the CASPS-652 6N ins/del polymorphism may affect the susceptibility to prostate cancer and reduce prostate cancer risk among Chinese men.

疫情或引发全球产业链重塑

一、美国十年期国债收益率跌至历史新低2020年2月29日,美国十年期国债收益率降至1.15%。尽管早在预料之内,但作为历史新低,这仍然可以看作是一个标志性事件。不过,金融市场无须对这一事件过度反应。因为,几乎可以确定,1.15%的新低纪录不久之后还会被再次刷新。在这一标志性事件面前,我们更需要思考的是,美债收益率的持续下跌反映了什么问题?能够带给我们什么启示?

A Numerical Study on Forecasting the Henan Extraordinarily Heavy Rainfall Event in August 1975

This study is essentially an experiment on the control experiment in the August 1975 catastrophe which was the heaviest rainfall in China's Mainland with a maximum 24-h rainfall of 1060.3 mm, and it significantly demonstrates that the limited area model can still skillfully give reasonable results even only the conventional data are available. For such a heavy rainfall event, a grid length of 90 km is too large while 45 km seems acceptable. Under these two grid sizes, the cumulus parameterization scheme is evidently superior to the explicit scheme since it restricts instabilities such as CISK to limited extent. The high resolution scheme for the boundary treatment does not improve forecasts significantly.The experiments also revealed some interesting phenomena such as the forecast rainfall being too small while affecting synoptic system so deep as compared with observations. Another example is the severe deformation of synoptic systems both in initial conditions and forecast fields in the presence of complicated topography. Besides, the fixed boundary condition utilized in the experiments along with current domain coverage set some limitations to the model performances.

TIBIALIS ANTERIOR VASCULARIZED TRIPLE FLAPS IN ONE STAGE RECONSTRUCTION OF MUTILATED HAND WITH LOSS OF THUMB

To introduce a one stage technique in the reconstruction of mutilated hand with loss of thumb and eventual digits. Methods Tibialis anterior pediculated triple flaps (TAPTF) including distal lateral leg, dorsalis pedis flaps for skin defect covering and trimmed hallux for thumb reconstruction were presented.Results Mutilated hands in five patients were repaired by the technique with acceptable cosmetic and functional success. A three to twelve months follow-up in three patients resulted in the recovery of protective thermal sensation and pinch action of the reconstructed thumb. The donor sites were free from major disability. Conclusion TAPTF is ideal for one stage reconstruction of the mutilated hand with loss of digits.

THE EARLY RESPONSE OF PIG SKIN TO FRACTIONATED DOSES OF 35 MeV P-Be FAST NEUTRONS IRRADIATION

The early responses of pig skin to fractionated doses of fast neutrons (35 Mev P→B) were determined. A neutron fractionation scheme comprised of 12 fractions in 42 days. The lowest doses of Ⅰ, Ⅱ, Ⅲ degree erythema of pig skin by Irradiation were 16. 38, 17. 32 and 19. 78 Gy respectively. The ED50 Values for moist desquamation was 23. 40 Gy. The mean latency of early pig skin damage was prolonged with the decreasing of total dose. The degree and the incidence of early pig skin damage were associated with total dose.These results for fast neutron therapy facility can be extrapolated to the human situation with a high degree of confidence, so that the neutron dose which would yield acceptable skin damage in patients may be determined using the data presented here.