Subjects: Geosciences >> Atmospheric Sciences submitted time 2023-12-16 Cooperative journals: 《干旱区研究》
Abstract： This study used the Sen+M-K trend analysis, the gravity center movement model, the standardizedregression coefficient, and the spatial clustering methods to reveal the spatial characteristics of the variation,trends, and movement of dust days of various types and the contribution rate of their influencing factors in theTarim Basin based on the annual data of 32 meteorological stations between 1964 and 2022. The resultsindicated: (1) Floating dust, followed by blowing sand and sandstorms, dominate the Tarim Basin, showing aspatial distribution pattern of more in the south and less in the north, and the dust days of various types showsignificantly decreasing trends. (2) The gravity centers of dust days of various types in the Tarim Basin tended tomove southeast, and the gravity center of sandstorm days moved the most. (3) Warmer temperatures, lower windspeeds, and fewer gale days were the main factors in the decreased dust days in the Tarim Basin, whereasprecipitation had the least influence. (4) The high contribution rates of precipitation to dust days are clustered inthe western part of the Tarim Basin, mean temperature and mean maximum temperature in the southern andwestern parts, respectively, and gale days and mean wind speed in the northwestern and southeastern parts,respectively. This study’s results can provide a scientific basis for developing regionally applicable windbreakingand sand-fixing measures in the Tarim Basin.
Subjects: Digital Publishing >> New Media submitted time 2023-10-08 Cooperative journals: 《中国传媒科技》
Abstract：Vlog作为记录生活的短视频新形式,已被越来越多的人群使用,并引起传媒行业的高度关注。融媒传播生态下,怎样把Vlog在新闻传播领域灵活运用,扩大新闻传播影响,提升媒体形象,成为专家学者的研究课题。本文通过分析Vlog新闻传播强调还原事实真相、不拘时长、极具个性特色、故事较完整、拍摄制作更专业的节目样态优势,从媒体视角提出地方传统媒体要加强本土化、扬长避短、做好前期策划、讲好新闻故事、增强节目黏性,依托 Vlog新闻优势开辟新的传播领域,吸引受众关注媒体发展的策略,为地方媒体从业人员灵活运用Vlog进行新闻报道提供参考。
Subjects: Digital Publishing >> New Media submitted time 2023-10-08 Cooperative journals: 《中国传媒科技》
Abstract：本文首先对新媒体的概念进行了阐释,而后分析了大数据背景下新媒体的特征,最后提出了大数据背景下传统媒体与新媒体融合的几种举措,以期为我国媒体行业的发展提供有建设性的参考。
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract： Hydrochloric dew point corrosion (DPC) behavior of 304 and 316L stainless steels was investigated using a novel DPC simulation set-up with in situ measurements of electrochemical impedance spectroscopy and electrochemical noise. The results indicated that the DPC resistance of 316L stainless steel was superior to 304. The difference of the corrosion performance for the two stainless steels can be ascribed to the following two aspects: the ratio of Cr/(Cr+Fe) is higher and the concentration of Fe is lower in the passive film of 316L stainless steel. There exists Mo in the passive film, which can enhance its pitting resistance of 316L stainless steel.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： The foreign academician system originating from Europe derives from the internationalization of the academician system and is also an important part of internationalization. Drawing on international practices, the foreign academician system of Chinese Academy of Sciences (CAS) was established in 1994 after a long and tortuous design process. With the development of globalization, foreign academicians have increasingly become an influential force in international cooperation and exchanges. To ensure the better functioning of foreign academicians, major western countries have formed effective mechanisms in their construction process. And our system has fully absorbed international experience and is also deeply rooted in the process of localization. The continuous improvement of comprehensive strength and the influence of the long history have formed our own characteristics. This work comparatively study the development and working mechanism of foreign academician systems. On this basis, some measures are put forward to further optimize the CAS's foreign academician system.
Subjects: Psychology >> Social Psychology submitted time 2023-03-27 Cooperative journals: 《心理学报》
Abstract： Under the influence of Darwin’s theory of biological evolution, instinct gradually became a core issue in the fields of human and animal psychology in the late 19th and early 20th centuries, soon to be relegated to the realm of “magic.” At the height of its popularity, theorists interpreted almost all human behavior in relation to instinct. A young Chinese developmental psychobiologist, Zing-yang Kuo, adopted John B. Watson’s approach to behaviorism, strongly advocating for the complete removal of instinct from the interpretation of human and animal behaviors - an approach that started a massive anti-instinct movement in the field of psychology in the United States. After returning to China, Kuo continued to spread his knowledge of radical behaviorism among the intellectual elite, promoting the debate on instinct, “one of the three biggest debates in the history of modern Chinese psychology.”Kuo’s suggestion that the origin of behavioral development could be traced in a laboratory setting was scorned by conservative US researchers. Convinced that he could resolve the controversy surrounding instinct in the laboratory, and following critical reflection on the matter, Kuo performed a range of experiments in China to verify his anti-instinct claims. Ultimately viewed as the most important development in the Chinese anti-instinct movement, Kuo’s work bridged the gaps in global debates on instinct. Psychologists such as Wei Joseph Ai, Shuh Pan, and Juefu Gao all joined the movement, and it also attracted the interests of other public intellectuals, including Jianren Zhou and Shicen Li.Centered on topics such as the existence of instinct, its definition, whether instincts are inherited, and the relationship between instincts, heredity, and environment, the heated discussion in China’s intellectual community surfaced positive, negative, and mixed reactions. While the Chinese anti-instinct movement did not develop extensive theories, there is no doubt that, as a natural extension of the international anti-instinct movement, it responded to the main contentions of the debate. While the Chinese movement expedited the methodological transmission of the psychological study of instinct from armchair to laboratory, it also confused the interpretation of development with that of evolution.While Kuo and the anti-instinct movement failed to “complete” their study of the psychology of instinct, their work revealed the epistemological value of semantics and the scientific method. Moreover, as a bridge between the global and Chinese anti-instinct movements, Kuo’s academic thought and scientific work reflect his uncompromising spirit of individualism and skepticism, which finally secured him a unique position in the history of behavioral science, exposed him to the wider fields of ethology, embryology, and development science, and provided the impetus for the positioning of “instinct” as an “unfinished” and open scientific issue.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-19 Cooperative journals: 《中国科学院院刊》
Abstract： Plant-derived natural products (PNPs) have been widely used in pharmaceutical and neutracuetical fields. Currently, extracting PNPs from their original plants is the main method to produce them. However, this extracting method is environmentally unfriendly, unsafe, and inefficient. Based on synthetic biology, construction of artificial cell factories for production of PNPs provides an alternative way. In this review, we focus on research progress for microbial production of terpenoids, alkaloids, and phenylpropanoids to give a brief introduction of construction of artificial cell factories for production of PNPs.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-19 Cooperative journals: 《金属学报》
Abstract： Hydrogen gas is usually included in coal gas environment, so hydrogen induced permeation would happen to pipeline, especially in welding heat affected zone (HAZ). Hydrogen permeation process in pipeline is the preconditions for the following hydrogen embrittlement failure. With the development of coal gas industry, the basic research to the hydrogen permeation behavior in pipeline under coal gas circumstance is still unfortunately lack and urgently needed to supplement. In this work, X80 pipeline steel was used, and the HAZ samples, including intercritical heat affected zone (ICHAZ), fine grained heat affected zone (FGHAZ) and coarse grained heat affected zone (CGHAZ), were experimentally simulated using a Gleeble 3500 simulator. Next, hydrogen permeation tests were conducted on X80 pipeline steel and HAZs in coal gas environment. Calculated results indicated that the hydrogen diffusion coefficient increased with the rise of peak temperature in HAZs, but it was opposite to other parameters, such as sub-surface hydrogen concentration, hydrogen solubility and hydrogen trap density. The mechanism of the difference in HAZ hydrogen permeation parameters was analyzed combined with OM, EBSD and TEM analysis. It turned out that the content of large-angle grain boundaries, the grain boundary straightness and dislocation density were the main factors, where the large-angle grain boundaries and dislocations could dramatically arrest hydrogen atoms while the straight grain boundaries may act as hydrogen diffusion path. For FGHAZ, the straight grain boundary and low dislocation density compared with matrix played the predominant role in hydrogen diffusion process, and thus the hydrogen diffusion coefficient increased compared with steel substrate. For ICHAZ and CGHAZ, the decrease of large-angle grain boundaries and dislocation density acted as the main factor, especially for CGHAZ, the microstructures was mainly composed of tabular bainite ferrite (BF) with large grain size and straight grain boundaries because of the highest peak temperature, and the content of large-angle grain boundaries decreased obviously. In comparation with other regions, CGHAZ had the highest hydrogen diffusion coefficient and the lowest hydrogen trap density and hydrogen solubility.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-19 Cooperative journals: 《金属学报》
Abstract： Amorphous alloy is a new type of material that exhibits exceptional properties or combinations of properties that are often not achievable in conventional crystalline materials. Fe-based amorphous alloys has attracted significant attention over the last few decades because of their low cost and enhanced mechanical performance. However, they are more suitable for the industrial application of coatings due to the fatal disadvantages of poor toughness. High velocity oxygen-fuel (HVOF) spraying is a good way to make amorphous alloy coatings (AMCs), for the individual droplets are cooled at a rate of around 107 K/s which is much higher than the critical cooling rate of the amorphous alloys during the thermal spraying. Fe-based AMCs obtained by using the HVOF spray method are important materials for industrial applications because of high glass- forming ability and exceptional performances, such as excellent corrosion resistance, high hardness, and superior wear resistance. In this work, Fe-CrMoMnWBCSi AMCs were prepared by HVOF thermal spray. The microstructure and amorphous characteristics of AMCs were characterized by SEM and XRD. Electrochemical corrosion behavior of AMCs was investigated in different concentration of NaCl and H2SO4 solutions compared with that of 304 stainless steel and ND steel. The surface film of materials after immersed in two solutions was analysed by XPS. The results indicated that HVOF thermal spraying Fe-based AMCs presented dense layered structure, high amorphous phase content and low porosity. The composite structure of AMCs was formed with some nanocrystallite phases embedded in the amorphous matrix. AMCs exhibited better resistance to pitting corrosion and relatively low uniform corrosion resistance due to the porosity, while the pitting potential of 304 stainless steel was sensitive to NaCl concentration. XPS results revealed that the presence of Cr, Mo and W oxides in the passive film of AMCs may result in the better corrosion resistance. The enrichment of Mo4+ oxides on the surface favored the formation of a more stable and protective layer which could be assumed to be responsible for the observed high stability of passive film. The diminishing or avording pores may be beneficial to further improve the pitting corrosion resistance of AMCs in NaCl solution. In all cases, AMCs showed better resistance to H2SO4 solutions corrosion due to the high stability of passive film. 304 stainless steel and ND steel presented stable passivation behavior only in high concentration of H2SO4 solution. In the lower concentration solution of H2SO4, the amorphous structure of the thinner coatings could facilitate the formation of thicker passivation film and lead to the higher corrosion resistance. The corrosion resistance of AMCs in H2SO4 solution could be enhanced significantly by formation of high amorphous phase.
Subjects: Biology >> Botany >> Applied botany submitted time 2022-07-05 Cooperative journals: 《广西植物》
Abstract： Liquidambar formosana is an excellent landscape ecological tree species because its beautiful tree shape and red or orange leaves in autumn. In order to understand the genetic basis of discoloration and secondary metabolism of L. formosana leaves, the mixed samples of L. formosana leaves at five discoloration periods were used for full-length transcriptome sequencing using single-molecule real-time sequencing technique (PacBio platform). The results were as follows: (1) High-quality 41.04 Gb data were obtained by full-length transcriptome sequencing, from which 563 180 full-length non-chimeric sequences were identified, and 27 269 high-quality full-length transcripts were obtained by clustering and de-redundancy. In 27 269 full-length transcripts, 2 035 long-chain non-coding RNA (lncRNA) were predicted, and 14 892 simple repeat sequence (SSR) sites and 1 856 transcription factors were detected. (2) The results of gene annotation showed that a total of 24 857 transcripts were annotated in 8 databases such as NR, GO, COG and KEGG, and 124 metabolic pathways were obtained in KEGG database, including ribosome, carbon metabolism, amino acid biosynthesis and so on. 49 and 71 transcripts were involved in flavonoid and chlorophyll metabolism respectively. The above results preliminarily reveal the transcriptome information and functional characteristics of L. formosana leaves during the discoloration period, and provide basic data for the follow-up study of the molecular mechanism of discoloration, the pathway and regulation of pigment metabolism and synthesis, the cloning of related functional genes and the improvement of leaf color.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2022-06-06 Cooperative journals: 《计算机应用研究》
Abstract： Aiming at the shortcomings of aquila optimization algorithm(AO) , this paper proposed an aquila optimization algorithm using hybrid search strategy. Firstly, the algorithm introduced dynamic adjustment function to balance global exploration and local exploitation; Secondly, it introduced chaotic adaptive weights to enhance the global search capability of the algorithm and accelerate the convergence speed of the algorithm; Thirdly, it introduced a new individual mutation probability coefficient and an improved differential mutation strategy, and used individuals with better fitness values to lead other individuals in the population to carry out search activities, which maintained the diversity of the population and enhanced the ability of the algorithm to jump out of the local optimum. Through the numerical experiment simulation of 8 benchmark test functions, 10 CEC2019 test functions and 1 engineering application problem, The experimental results show that the algorithm has a significant improvement in global convergence speed and optimization accuracy, and has a better ability to jump out of the local optimum.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2022-05-10 Cooperative journals: 《计算机应用研究》
Abstract： Action recognition(AR) is a hot research area in computer vision field, and has an extensive application prospect for security monitoring, autopilot, production safety etc. Firstly, this paper analysed the connotation and denotation of AR and put forward the technical challenges; Secondly, the paper analysed and compared the working principles of AR from three aspects: time feature extraction, efficient optimization and long-term feature capture; Thirdly, in order to select suitable AR models for different application scenarios, this paper compared the performance characterization of 43 benchmark AR methods in recent ten years based on UCF101, HMDB51, Something-Something and Kinetics400 data sets. Finally, this paper pointed out the future development direction of AR field, and the research results can provide theoretical reference and technical support for video feature extraction and visual content understanding.
Subjects: Geosciences >> Geography submitted time 2020-11-24 Cooperative journals: 《干旱区地理》
Abstract： 利用新疆1954—2018年雪灾资料分析其灾害时空特征，时间上雪灾灾损强度在90年代后出现明显加大，2010年出现跃增特点，空间上雪灾灾损强度新疆西部多于东部，北部多于南部，山区多于盆地或平原。用雪灾出现次数、房屋倒塌间数、牲畜棚圈倒塌间数、损坏大棚数、死亡牲畜数、受灾面积、经济损失等多指标综合分析法来客观构建灾损指数，符合[Γ分布的灾损指数结合F分布函数能客观的描绘出雪灾等级，分为一般、较重、严重、特重4个等级。根据构建的雪灾等级，发现新疆雪灾特重灾区集中在天山山区及其以北地区，南疆仅有喀什地区为特重灾区。
Subjects: Geosciences >> Geography submitted time 2020-06-02 Cooperative journals: 《干旱区地理》
Abstract： 风云三号D星(FY-3 D)是我国新一代极轨气象卫星，中分辨率光谱成像仪II ( MERSI- II )是其携带的核心传感器之一，MERSI- }实现了云、气溶胶、水汽、陆地表面特性、海洋水色等大气、陆地、海洋参量的高精度定量反演。选取2018年大8月无云时相的FY-3 D/MERSI- II数据对天山中段终年积雪进行归一化积雪指数(vDSI)的计算。结合高分辨率Landsat-8影像，利用混淆矩阵对FY-3D/MERSI- II数据计算结果与同期MODIS日积雪产品数据MOD10A1进行精度对比分析。结果表明:FY-3 D/MERSI- II图像平均总体精度为0. 855 , MOD10A1图像平均总体精度为0. 820 ,FY-3 D/MERSI- }积雪覆盖提取平均总体精度比MOD10A1积雪覆盖提取平均总体精度高0. 035FY-3 D/MERSI- II的K内>pa系数平均值为0. 659 , MOD10A1的K句>pa系数平均值为0. 558 , FY-3 D/MERSI- II的K内>pa系数平均值大于MOD10A1的K内>pa系数平均值。故FY-3 D/MERSI- II数据提取积雪覆盖面积精度更高，更接近高分辨率Landsat-8影像目视解译结果。
Subjects: Geosciences >> Geography submitted time 2020-01-06 Cooperative journals: 《干旱区地理》
Abstract：利用2010—2017年1~12月新疆喀什地区10个气象站逐小时降水资料，分析统计喀什地区近8 a降雨雪（以下统称降水）日变化特征。结果表明：（1） 喀什地区全年降水量和降水频次日变化存在明显的波动，总体上呈现“正弦波”一峰一谷特征，降水量峰值出现在03:00（北京时，下同），谷值出现在18:00；降水频次峰值出现在04:00，谷值出现在18:00；两者峰谷值出现时间接近。（2） 2010—2017年喀什地区全年降水量和降水频次呈明显的增加趋势；而降水强度年际变化趋于平缓，无明显变化。（3） 降水强度日变化趋势与降水量、降水频次并不存在一致性。（4） 喀什地区全年降水主要以短时段降水为主，其中，持续1 h降水次数为最大值，但降水量和贡献率最大值却同出现在2 h和6 h持续降水中。全年降水主要以后半夜和上午开始的降水过程为主导，且仍主要为短时段降水。
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To explore the expression of CDK6 in early ovarian cancer and explore its clinical significance. Methods Real-time PCR and immunohistochemistry was used to examine the differential expression of CDK6 mRNA and protein in ovarian cancer and normal ovarian tissues. The correlation of CDK6 expression with the clinical characteristics and prognosis of the patients was analyzed. Results The expression of CDK6 mRNAwas obviously up-regulated in 36 ovarian cancer tissues as compared to that in 16 ovarian tissues. Immunohistochemistry demonstrated that CDK6 protein was expressed in both the cytoplasm and cell nuclei. Compared with the 48 normal ovarian tissues, the 121 ovarian cancer tissues showed significantly up-regulated CDK6 protein expression (P=0.044). Increased CDK6 protein expression was not significantly correlated with the clinical features of the patients with ovarian cancer, but showed a significant negative correlation with the patients' prognosis (P=0.006). Multivariate analysis suggested that CDK6 expression level was an independent prognostic indicator (P=0.008) for the survival of patients with ovarian cancer. Conclusion Increased CDK6 protein expression may promote the development andprogressionofearlyovariancancer.
Subjects: Materials Science >> Materials Science (General) submitted time 2016-11-14 Cooperative journals: 《中国腐蚀与防护学报》
Abstract：本文采用双极性脉冲电源，在一定的阳极电流密度(ja)下，改变制备过程中阴极电流密度(jc)的大小，在LY12铝合金表面制备微弧氧化膜。采用扫描电镜(SEM)、电化学阻抗谱(EIS)以及中性盐雾试验研究微弧氧化膜的表面微观形貌、致密性以及实际服役性能的变化，进而分析阴极电流密度jc的变化对LY12铝合金微弧氧化膜致密性的影响。结果表明：阴极电流密度的大小对于微弧氧化膜的致密性具有至关重要的影响，施加适当的阴极电流密度可以制备致密性较好的氧化膜；当阴极电流密度较低或较高时，微等离子体在基体表面放电火花分布不均，无法获得致密性氧化膜；当ja=5A/dm2，ja/jc=1:1时，获得的LY12铝合金微弧氧化膜的致密性最佳。
Subjects: Materials Science >> Materials Science (General) submitted time 2016-11-11 Cooperative journals: 《中国腐蚀与防护学报》
Abstract：采用阴极极化条件下的氢渗透实验和慢应变速率拉伸实验研究了X65钢在模拟海水中的氢渗透行为及其对断裂机理的影响。氢渗透实验结果表明，阴极极化过程中试样表面的钙镁沉积层能显著地降低氢扩散系数，采用Fourier方程、Laplace方程以及时间滞后法计算得出的有效氢扩散系数平均值为1.49×10-7 cm2·s-1。结合变电位极化氢渗透测试结果、拉伸试样断口分析以及极化曲线测试，对阴极极化条件下X65钢的氢脆敏感性进行评估，结果显示，随着极化电位的降低，X65钢中的吸附氢浓度呈指数规律上升。当极化电位较高时，X65钢的裂纹扩展受阳极溶解和阴极析氢的双重作用控制。当极化电位较低，如-1200 mV时，钢中的吸附氢浓度急剧增加，脆性断裂区域的比例上升，X65钢发生氢致脆化失效。
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