Simple synthesis of silver nanocluster composites AgNCs@PE-g-PAA by irradiation method and fluorescence detection of Cr^(3+)

Silver nanoclusters(AgNCs)are a new type of nanomaterials with similar properties to molecules and unique applications.The applications of AgNCs can be significantly expanded by combining them with different matrix materials to obtain AgNC composites.Using irradiation techniques,we developed a simple two-step method for preparing silver nanocluster composites.First,polyacrylic acid(PAA)chains were grafted onto the surface of a PE film as templates(PE-g-PAA).Subsequently,silver ions were reduced in situ on the surface of the template material to obtain the AgNC composites(AgNCs@PE-g-PAA).The degree of AgNC loading on the composite film was easily controlled by adjusting the reaction conditions.The loaded AgNCs were anchored to the carboxyl groups of the PAA and wrapped in the graft chain.The particle size of the AgNCs was only 4.38±0.85 nm,with a very uniform particle size distribution.The AgNCs@PE-g-PAA exhibited fluorescence characteristics derived from the AgNCs.The fluorescence of the AgNCs@PE-g-PAA was easily quenched by Cr^(3+)ions.The composite can be used as a fluorescence test paper to realize visual detection of Cr^(3+).

Preparation of antibacterial non-woven AgNCs@PP-g-PAA via radiation method

With the growing threat of airborne epidemics,there has been an increasing emphasis on personal protection.Masks serve as our primary external defense against bacteria and viruses that might enter the respiratory tract.Hence,it’s crucial to develop a polypropylene(PP)nonwoven fabric with quick antibacterial capabilities as a key component for masks.This study introduces silver nanoclusters(AgNCs)into non-woven PP using radiation technology to infuse antibacterial properties.Initially,a solid ligand(PP-g-PAA)was procured via radiation grafting of the ligand polyacrylic acid(PAA),which was incorporated into the nonwoven PP with the aid of a crosslinking agent at a lower absorbed dosage.Subsequently,AgNCs were synthesized in situ on PP-g-PAA via an interaction between PAA and AgNCs,leading directly to the formation of AgNCs@PP-g-PAA composites.Owing to the hydrophilicity of PAA,AgNCs@PP-g-PAA maintains good moisture permeability even when the voids are heavily saturated with PAA gel,preventing droplet aggregation by diffusing droplets on the surface of the material.This feature enhances the comfort of the masks.Most importantly,due to the incorporation of AgNCs,AgNCs@PP-g-PAA demonstrates outstanding antibacterial effects against Escherichia coli and Staphylococcus aureus,nearly achieving an instant“touch and kill”outcome.In conclusion,we synthesized a modified nonwoven fabric with significant antibacterial activity using a simple synthetic route,offering a promising material that provides improved personal protection.

Superior corrosion resistance-dependent laser energy density in(CoCrFeNi)95Nb5 high entropy alloy coating fabricated by laser cladding

(CoCrFeNi)95Nb5 high entropy alloy(HEA)coatings were successfully fabricated on a substrate of Q235 steel by laser cladding technology.These(CoCrFeNi)95Nb5 HEA coatings possess excellent properties,particularly corrosion resistance,which is clearly superior to that of some typical bulk HEA and common engineering alloys.In order to obtain appropriate laser cladding preparation process parameters,the effects of laser energy density on the microstructure,microhardness,and corrosion resistance of(CoCrFeNi)95Nb5 HEA coating were closely studied.Results showed that as the laser energy density increases,precipitation of the Laves phase in(CoCrFeNi)95Nb5 HEA coating gradually decreases,and diffusion of the Fe element in the substrate intensifies,affecting the integrity of the(CoCrFeNi)95Nb5 HEA.This decreases the microhardness of(CoCrFeNi)95Nb5 HEA coatings.Moreover,the relative content of Cr2O3,Cr(OH)3,and Nb2O5 in the surface passive film of the coating decreases with increasing energy density,causing corrosion resistance to decrease.This study demonstrates the controllability of a high-performance HEA coating using laser cladding technology,which has significance for the laser cladding preparation of other CoCrFeNi-system HEA coatings.

Anti-penetration performance of high entropy alloy–ceramic gradient composites

A high-entropy alloy–ceramic gradient composite of TiC–TiB_2/75vol% Al_(0.3) CoCrFe Ni was successfully prepared by combustion synthesis under an ultra-high gravity field, which is a low-cost method with high efficiency. The ceramic particles were gradient distributed in the Al_(0.3) CoCrFe Ni matrix, and the hardness of the composite material gradually decreased along the thickness direction. The anti-penetration performance of the gradient composites was simulated using the ANSYS/LS-DYNA explicit simulation program. The results demonstrate that the distribution of the ceramic particles strongly affected the mechanical properties and the anti-penetration performance of the composites. With the same total ceramic volume fraction, the gradient composites exhibit better anti-penetration performance than the corresponding ceramic–metal interlayer composites. The more uneven the ceramic distribution, the greater the elastic modulus and yield stress of the surface layer and, thus, the better the anti-penetration performance.

Dynamic characteristics of the planetary gear train excited by time-varying meshing stiffness in the wind turbine

Wind power has attracted increasing attention as a renewable and clean energy. Gear fault frequently occurs under extreme environment and complex loads. The time-varying meshing stiffness is one of the main excitations. This study proposes a 5 degree-of-freedom torsional vibration model for the planetary gear system. The influence of some parameters(e.g., contact ratio and phase difference) is discussed under different conditions of a single teeth pair and double pairs of teeth. The impact load caused by the teeth face fault, ramped load induced by the complex wind conditions, and the harmonic excitation are investigated. The analysis of the time-varying meshing stiffness and the dynamic meshing force shows that the dynamic design under different loads can be made to avoid resonance, can provide the basis for the gear fault location of a wind turbine, and distinguish the fault characteristics from the vibration signals.

间充质干细胞源性外泌体抑制创伤性脑损伤炎症反应的研究进展

中国每年约有80万新发创伤性脑损伤(TBI)患者,其中重度患者死亡率约为27%,是青壮年死亡和致残的首要原因,为社会及家庭带来极大影响。TBI按病理、生理机制分为原发性脑损伤和继发性脑损伤。原发性脑损伤是机械性致伤因素的直接结果,而继发性脑损伤是在原有脑损伤基础上,颅外损伤与颅内物理、生化变化的总和,与TBI预后有重要关系。其中神经炎症反应所引起的一系列分子、细胞、组织器官水平级联反应在继发性脑损伤形成中有重要作用。目前间充质干细胞源性外泌体(MSC-Exo)作为脑损伤极具前景的治疗方式,可有效减轻神经炎症反应,改善TBI预后。该文就MSC-Exo抑制TBI后神经炎症反应的作用机制及其治疗前景作一综述,以期为后续的研究和治疗提供一定的参考。

A new lunar absolute control point: established by images from the landing camera on Chang'e-3

The establishment of a lunar control network is one of the core tasks in selenodesy, in which defining an absolute control point on the Moon is the most important step. However, up to now, the number of absolute control points has been very sparse. These absolute control points have mainly been lunar laser ranging retroreflectors, whose geographical location can be observed by observations on Earth and also identified in high resolution lunar satellite images. The Chang'e-3(CE-3) probe successfully landed on the Moon, and its geographical location has been monitored by an observing station on Earth. Since its positional accuracy is expected to reach the meter level, the CE-3 landing site can become a new high precision absolute control point. We use a sequence of images taken from the landing camera, as well as satellite images taken by CE-1 and CE-2, to identify the location of the CE-3 lander. With its geographical location known, the CE-3 landing site can be established as a new absolute control point, which will effectively expand the current area of the lunar absolute control network by 22%, and can greatly facilitate future research in the field of lunar surveying and mapping, as well as selenodesy.

Terrain reconstruction from Chang'e-3 PCAM images

The existing terrain models that describe the local lunar surface have limited resolution and accuracy, which can hardly meet the needs of rover navigation,positioning and geological analysis. China launched the lunar probe Chang'e-3 in December, 2013. Chang'e-3 encompassed a lander and a lunar rover called "Yutu"(Jade Rabbit). A set of panoramic cameras were installed on the rover mast. After acquiring panoramic images of four sites that were explored, the terrain models of the local lunar surface with resolution of 0.02 m were reconstructed. Compared with other data sources, the models derived from Chang'e-3 data were clear and accurate enough that they could be used to plan the route of Yutu.

Powder metallurgy of high-entropy alloys and related composites: A short review

High-entropy alloys(HEAs)have attracted increasing attention because of their unique properties,including high strength,hardness,chemical stability,and good wear resistance.Powder metallurgy is one of the most important methods used to fabricate HEA materials.This paper introduces the methods used to synthesize HEA powders and consolidate HEA bulk.The phase transformation,microstructural evolution,and mechanical properties of HEAs obtained by powder metallurgy are summarized.We also address HEA-related materials such as ceramic–HEA cermets and HEA-based composites fabricated by powder metallurgy.

Moxibustion treatment for knee osteoarthritis： cumulative meta-analysis and trial sequential analysis

目的：采用累积Meta分析方法评价艾灸在膝骨关节炎患者中的应用效果，并运用试验序贯分析检验Meta分析结果的真实性。方法：计算机检索PubMed、EMbase、The Cochrane Library、CNKI和CBM数据库中关于艾灸和药物疗法应用于膝骨关节炎患者的随机对照试验。筛选文献、数据提取、纳入文献的评价均由两名评价者独立进行，核对无误后运用Stata11．0软件进行数据分析。结果：最终纳入11篇文献，包括1005例患者。Meta分析结果显示，在VAS评分上差异无统计学意义[SMD=-1．07，95％CI（-2．18，0．04）]，在有效率[OR=O．40，95％CI（0．27，0．60）]和膝关节评分[SMD_-0．70，95％CI（-1．22，-0．19）]上艾灸疗法优于药物组。试验序贯分析结果表明，在VAS指标上样本量未达到试验序贯分析界值，在有效率方面样本量达到RIS，在膝关节评分上样本量在达到RIs前已获得肯定结果。结论：艾灸疗法在治疗膝骨关节炎上效果优于药物疗法。但仍需要大样本、高质量的随机对照试验进行验证。

Colorectal cancer mortality in Inner Mongolia between 2008 and 2012

AIM: To determine the extent of colorectal cancer(CRC) mortality and the association between demographic characteristics and CRC mortality in Inner Mongolia.METHODS: Data were collected from the Death Registry System, maintained by the Inner Mongolia Centers for Disease Control and Prevention, from 2008 to 2012. Deaths were classified according to the International Classification of Disease, 10th Revision. Years of life lost, average years of life lost(AYLL), and mortality were calculated over the five years between 2008 and 2012. A conditional logistic regression model was used to analyze the association between marital status, occupational status, education level, area of residence, and the risk of CRC.RESULTS: The AYLL of CRC was 17.39 years. The average mortality of CRC was 5.6/100000. People living in urban areas and having a higher education level had a significantly higher risk of CRC(OR = 1.74 and 95%CI: 1.29-2.35, P < 0.001 and OR = 2.39, 95%CI: 1.76-3.25, P < 0.001, respectively). People who were employed had a lower risk of CRC(OR = 0.64, 95%CI: 0.48-0.86, P = 0.003). The mortality of CRC was positively correlated with the education level(P < 0.001). No statistically significant association was observed between marital status and CRC risk(P = 0.259).CONCLUSION: Living in urban areas, higher education level and unemployment are associated with CRC mortality in Inner Mongolia.

Characteristics of a coherent jet enshrouded in a supersonic fuel gas

Based on a current coherent jet,this study proposes a supersonic combustion(SC)coherent jet in which the main oxygen jet is surrounded by a supersonic fuel gas.The characteristics of the proposed coherent jet are analyzed using experimental methods and numerical simulations in the high-temperature environment of electric arc furnace(EAF)steelmaking.The SC coherent jet achieved stable combustion in the EAF steelmaking environment.The simulated combustion temperature of the supersonic shrouding methane gas was 2930 K,slightly below the theoretical combustion temperature of methane–oxygen gas.The high speed and temperature of the supersonic flame effectively weakened the interaction between the main oxygen jet and the external ambient gas,inhibiting the radial expansion of the main oxygen jet and maintaining its high speed and low turbulence over a long distance.These features improved the impact capacity of the coherent jet and strengthened the stirring intensity in the EAF bath.

Research progress of diabetes treatment guided by Traditional Chinese Medicine constitutional types

Diabetes and its complications seriously affect patients’life quality,and have a major impact on individuals,families,health systems,and national economies.Traditional Chinese Medicine constitution refers to the inherent characteristics of a relatively comprehensive and stable form,structure,physiological function,and psychological state formed under the combined effects of innate endowments and acquired in the course of an individual’s life.Many studies have shown that the constitution type is closely related to the incidence of diabetes,especially in the process of disease prevention and treatment.This article reviews the correlation of diabetes and its chronic complications with constitution types to provide theoretical basis for the treatment of diabetes based on syndrome differentiation.

Opportunities and challenges for the development of traditional Chinese medicinenursing under the new healthcare reform

随着医疗卫生改革的不断深化和人民群众对中医药服务需求的增加,中医药在卫生体制改革中的势逐步突显.中医护理作为中医药健康服务业的重要组成部分,其规范化、专业化的发展问题一直到业内学者和社会的广泛关注.文章通过对《关于深化医药卫生体制改革的意见》、《中医药发展略规划纲要（2016-2030年）》和国家中医药管理局发布的相关政策及中医护理发展相关文献的解读,章分析了新医改形势下中医护理在专业化发展过程中面临的机遇和挑战,并对其进行分析,以期为医护理专业化发展道路提供借鉴.

The Application Progress of Auricular Therapy in Diabetes

Diabetes,as a chronic incurable disease,not only causes acute complications such as hyperglycemic hyperosmolar status,ketoacidosis and hypoglycemia,but also affects arteries and nervous system,causing the eyes,kidneys,feet,blood vessels,nerves and other organs or tissues damage,and leading to the occurrence and development of chronic diseases.The World Health Organization believes that diabetes may be the most important non-communicable global disease caused by unhealthy modern lifestyles and regards it as a major global health problem.At present,there is still a lack of specific drugs for the treatment of diabetes,and related treatment drugs are often accompanied by adverse reactions.Auricular therapy as a non-drug,non-invasive treatment method show unique advantages in the treatment of diabetes.This article reviews the mechanism of auricular therapy and its application status in diabetes,in order to broaden the mind for the auricular therapy to treat diabetes.

Tuning Acceptor Length in Photocatalytic Donor-Acceptor Conjugated Polymers for Efficient Solar-to-Hydrogen Energy Conversion

The development of conjugated polymer photocatalysts for efficient solar-to-hydrogen energy conversion is highly desirable for the sustainability of our society.Although the construction of donor-acceptor(D-A)structure in conjugated polymer photocatalysts for solar-to-hydrogen energy conversion has been well documented,less attention has been paid on how large D and how large A units combined together could achieve the best performance.Herein,a series of D-A copolymers P(BDT-DBTSOx)(x=7,19,39,and 79)composed of a benzodithiophene(BDT)donor unit and an oligomeric dibenzo[b,d]thiophene sulfone(DBTSO)acceptor segment were synthesized and studied.It was found that the polymer photocatalytic stabilities under full-arc irradiation improved upon shortening the length of the acceptor segment.Under visible light irradiation and in the presence of 3 wt%Pt cocatalyst,P(BDT-DBTSO79)displayed the best performance with an optimal hydrogen evolution rate of 119.3±5.8 mmol·g^(-1)·h^(-1).This is 1.4-fold as that of DBTSO homopolymer and 22.5-fold as that of BDT/DBTSO alternative copolymer,highlighting the importance of acceptor length in D-A structure for achieving high photocatalytic performance.