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The effect of the applied electric field on the diffusion activation energy of Cu crystal was studied by the first-principles calculation and current assisted sintering. The results show that the applied electric field and current reduce the difficulty of Cu vacancy generation, but the atomic migration energy is almost unchanged, resulting in a slight decrease in diffusion activation energy after reaching the electric field intensity (current density) threshold (2 V·Å‒1 (307.1 A·cm‒2)), and a sharp decrease after exceeding the threshold; finally, after the electric field intensity (current density) reaching 5 V·Å‒1 (708.5 A·cm‒2), the vacancy formation energy gradually decreases to 0, the diffusion activation energy drops to the critical value, and the critical value of diffusion activation energy decreases by about 60.2% compared with that of the threshold value. The diffusion activation energy shows a regular decline trend under the action of electric field or current, and the experimental results show a good positive correlation with the first-principle simulation results.

The microstructure morphology， low-temperature performance， and corrosion resistance of hot-rolled and normalized condition Gr.6 steel pipes were analyzed using optical microscopy， scanning electron microscopy， transmission electron microscopy， mechanical testing， and corrosion testing. The results show that the low-temperature mechanical properties and corrosion resistance of the developed low-temperature seamless steel pipe Gr.6 in the hot-rolled and normalized states meet the standard requirements. The microstructure in the hot-rolled state is pearlite and ferrite， with uniform and fine grains， but the banded structure is obvious.The precipitated phase is mainly composed of TiN particles， which undergo a ductile brittle transition at -60 ℃. After 900 ℃ normalizing heat treatment， the grains become finer， with a grain size of 10 grade or above. The proportion of large angle grain boundary differences in the normalized state sample is higher than that in the hot-rolled state， and the density of the large angle interface also increases. The precipitate phase is mainly TiN and a small amount of VN particles， and no ductile brittle transition has occurred at -80 ℃.The corrosion behavior of the material was studied through polarization tests with fast and slow polarization scanning rates. Corrosion tests have shown that the stress corrosion sensitivity of normalized specimens is relatively low in electrochemical simulation solutions， while the stress corrosion sensitivity of hot-rolled specimens is relatively high. Therefore， the electrochemical corrosion performance of the normalized state is better than that of the hot-rolled state， and it is suitable for more harsh corrosion environments.

Objective To evaluate the clinical efficacy of clear aligner for crowded dentition in early permanent teeth by moving the upper and lower molars far. Methods A total of 36 adolescent patients with Class Ⅰ Angle malocclusion admitted in our department from March 2017 to August 2023 were enrolled, and they were 17 males and 19 females, and at a mean age of 13.20±0.53 years. Clear aligner was applied to push the upper and lower molars backward to obtain a neat dentition. Lateral cephalometric X-ray film before and after treatment was measured, and paired t-test was used to compare the cephalometric measurements before and after treatment. Results The average course of treatment was 21.2 months. Overbite, overjet and molar relationship were turned to normal after treatment, and the soft tissue profile was maintained. Analysis of relevant cephalometric items showed that the Ptm-U6 distance was decreased by 2.89±1.22 mm, and the Go-L6 distance was decreased by 2.61±1.07 mm after treatment, with significant differences (P < 0.01). While, there were no statistically differences in UL-EP, LL-EP, NLA and FCA before and after treatment. Conclusion With reasonable treatment target and good tooth movement design, clear aligner can effectively move the upper and lower molar distally to correct moderate dentition congestion in early permanent teeth, and meanwhile the patients' profile is maintained.

Alzheimer's disease(AD), the most common neurodegenerative disease, has shown an increasing incidence among younger people. With the onset of disease, most patients' cognitive function will show a progressive decline, bringing a heavy burden to the society and the family. Studies have shown that fibroblast growth factor (FGF) may be involved in the pathogenesis of AD through multiple mechanisms. This article reviews the mechanism of FGF in AD, with the hope of providing new ideas for elucidating the pathogenesis and early diagnosis of AD.

In response to the impact of the widespread integration of new energy sources on the secure operation of distribution networks， a study is undertaken to explore a multi-time scale interactive strategy for distributed electro-hydrogen coupled systems， incorporating hybrid energy storage and distribution networks. Firstly， interactive mechanisms including the balancing service mechanism and demand response mechanism between distributed electro-hydrogen coupled systems and distribution networks are proposed. Secondly， based on game theory， medium-to-long-term and short-term interactive strategies are formulated for electro-hydrogen coupled systems and distribution networks. Finally， a simulation analysis is executed utilizing the distribution networks and distributed electro-hydrogen coupled system in a representative region as an illustrative example. The outcomes of the case study underscore that hydrogen storage exhibits an advantage in medium-to-long-term interactions due to its cross-period characteristics. Electrochemical storage， distinguished by its rapid response， proves more suitable for short-term interactions. In comparison to singular energy storage systems， a hybrid electro-hydrogen storage system can effectively mitigate difference between peak and valley loads， enhancing system benefits， and seamlessly aligning with the existing distribution network system.

Camellia minima, a rare and endangered species of sect. Chrysantha, has not been previously explored in terms of its chloroplast genome. Utilizing the Illumina HiSeq 2000 platform, the chloroplast genome sequence of C. minima was sequenced, assembled, annotated, and analysed. The results were as follows: (1) The chloroplast genome of C. minima was 156 961 bp in length, embodied a typical tetrad structure, and contained 136 annotated genes, including 87 protein-coding genes, 41 tRNA genes, and 8 rRNA genes. (2) The analysis identified 66 SSR loci and 39 repetitive sequences. (3) Codons prefered to use codons ending in A/U. Comprehensive effective number of codons (ENC) mapping, PR2-plot, and neutral analyses suggested natural selection as a primary factor shaping codon usage patterns. (4) Boundary analysis showed variation in the length and position of the ycf1 gene among different species of yellow Camellia. (5) Phylogenetic analysis of the chloroplast genomes of published sect. Chrysantha species revealed that C. minima was most closely related to C. micrantha. This study provides crucial references for exploring species evolution and enhancing exogenous gene expression, establishing a theoretical foundation for the conservation and utilization of species of sect. Chrysantha in the future.

To alleviate the increasingly severe global warming problem and achieve carbon neutrality goals, the carbon capture, utilization, and storage (CCUS) technology has attracted widespread attention as an important breakthrough direction. High-performance adsorption separation technology is the key to the implementation of CCUS technology. For the currently largest and most difficult-to-handle low-concentration CO_2 emission, such as direct capture of CO_2 from air, considering factors such as capture energy consumption and cost, pressure swing adsorption has obvious advantages over chemical absorption, membrane separation, or other technologies. The selection of suitable adsorption materials is crucial. This article reviews several main types of CO_2 solid porous adsorbents at present stage, including carbon materials, metal-organic frameworks (MOFs), molecular sieves, amine-modified solid porous materials, and polyionic liquids, expounds their related research progress and existing problems in CO_2 capture process, and briefly introduces the subsequent industrial applications. The issues for current low concentration CO_2 capture technologies to be addressed are associated with the adsorbent regeneration and diffusion problems and the prospects for the conversion and reuse process of captured CO_2.

As renewable energy with no pollution but wide sources and high calorific value， hydrogen becomes increasingly important in the context of energy shortage and dual carbon goals. The safety of liquid hydrogen is an important factor impeding its application. In this regard， the research results of worldwide liquid hydrogen safety in recent years are summarized. The hazards of liquid hydrogen are discussed in view of its low temperature， leakage， and combustion. The research results of the liquid hydrogen leakage and dispersion law from experimental and numerical simulations are introduced. The latest research progress of liquid hydrogen safety protection measures is outlined. Overall， the hazards of liquid hydrogen have now been fully understood， but liquid hydrogen leakage and dispersion laws must be further studied. There are few experimental data on liquid hydrogen leakage and dispersion， and the related numerical simulations still face many difficulties. No comprehensive standards， laws， and regulations are yet formulated for the safety requirements of liquid hydrogen storage， transportation and application.

The hydrogen energy storage technology based on the electric-hydrogen conversion mechanisms can realize wind and PV power consumption， smooth out wind and PV power fluctuations， and thus can be used as an important form of renewable energy power generation support. The construction of multivariate simulation models is an important means to promote the design and control of a wind-PV-hydrogen coupling system. The mechanistic models and common simplified models of wind power generation， photovoltaic power generation， and hydrogen production through electrolysis are introduced. The coupling characteristics of different renewable energy generation and hydrogen production are compared. Moreover， the application value of simulation models in operation and control optimization， source-grid-load interaction， and capacity configuration is illustrated based on domestic and foreign modeling cases. In view of the present technology development， the development of technology is analyzed and foreseen concerning the multi-physical field， multi-time scale， and multi-element to guide and facilitate the construction of related platforms and projects to accelerate the energy mix transformation towards zero-carbon energy supply and green energy use through the review of the basis for modeling of coupled hydrogen production from renewable energy sources.

Steamed bread is one of the traditional Chinese staple foods. With the increasing in the proportion of mechanized production and market-oriented sales of steamed bread, the steamed bread industry has been developing rapidly. Under the production conditions of industrial steamed bread, the characteristics of wheat varieties and their corresponding flour suitability for making steamed bread, especially the stability of flour, could significantly affect the product quality, consumption experience and economic benefits of industrialized steamed bread. In this study, the physical and chemical properties of flours from wheat varieties with larger planting area and stronger representatives in southwest Henan were analyzed for the suitability of steamed bread, and the relationships between flour and steamed bread quality properties were also studied. The results showed that the wet gluten content of wheat flour in southwest Henan was high, but the gluten index needed to be improved. The proportion of strong-gluten wheat variety also needed to be improved. The values of flour color a* b *, gluten index, the dough softening by Farinograph, the area by Extensograph and the extensibility (L) by Alveograph are important reference indicators for evaluating the quality of flour for steamed bread. The wheat varieties of Zhengmai 119, Pingmai 998, Shaanxi Road 198, Zhengmai 1342, and Zhengmai 1860 are more suitable for making steamed breads.

Through the chain operation of the catering for the Lanzhou ramen noodles (hand-extended noodles) traditional noodle products become a model for brand management and a sample of product-driven catering industrial development. In the process of Lanzhou ramen chain operation, the supply of wheat flour suitable for making Lanzhou ramen and flour standardization are one of the main problems affecting business benefit and product quality. Milling companies need wheat ingredients and flour standards for making Lanzhou ramen. Flours of wheat varieties mainly cultivated in Guanzhong Plain were used as raw materials, the ramen was made by professional ramen masters. The ramen were evaluated by full-time food sensory evaluators, so wheat flour suitable for making Lanzhou ramen is screened out to provide a reference basis for the formulation of ramen standards. The results showed that in the sensory evaluation of ramen making process, the ramen master was more sensitive to “Extending force”, followed by “Degree of mixing and hardness of dough”. The wheat varieties of Xinong 583, Zhengmai 366, Weilong 169, Xinong 822, Bainong 207 and Zhongmai 578 as samples were more suitable for making Lanzhou ramen. It was found that the total sensory evaluation score of the ramen making process was closely related to the Alveograph parameters, while the total sensory evaluation score of the ramen product after cooking was closely related to the Extensograph parameters.

The traditional RGB-based action recognition method is vulnerable to background factors such as illumination and occlusion, which makes the recognition accuracy and real-time performance low. In order to solve the above problems, a 2D skeleton action recognition method incorporating a hierarchical attention mechanism was proposed. Firstly, the human skeleton joints in the video were extracted using the human pose estimation algorithm OpenPose. Secondly, the missing and abnormal points in the extracted skeleton data were pre-processed by the mean-completion method and exponential smoothing method. Finally, a network model based on CNN-LSTM fused with hierarchical attention mechanism, CNN-HALSTM, was constructed to realize action classification. The results show that the recognition accuracy of this method in interactive motion and KTH data sets is 96.73% and 98.35%, and the model parameters are significantly reduced, which has the advantage of real-time performance and is better than other methods of the same type.

The effects of long term ageing on the size and morphology of γ' precipitations in the spray formed nickel-based superalloy FGH100L after subsolvs and supersolvs heat treatment (HT) were studied by scanning electron microscope (SEM). The results show that there are four kinds of γ' phases in the alloys after the subsolvs HT, and during the long term ageing, the sizes of primary, secondary, and large tertiary γ' phases increase while the size of small tertiary γ' phase decreases. None of these γ' phases grow in accordance with the coarsening kinetics as the Lifshitz, Slyozov, and Wagner (LWS) theory during the long term ageing. Apart from the small tertiary γ' phase, other three kinds of γ' phases began splitting in a similar way, and the secondary γ' phase shows the unstable protrusion after ageing for 500 h. No topological close packed (TCP) phase is found in the subsolvs HTed alloys. There are three kinds of γ' phases in the alloys after the supersolvs HT, and during the long term ageing, the primary γ' phase grows up slightly while the secondary and tertiary γ' phases show no obvious change. None of these γ' phases grow in accordance with the coarsening kinetics as LWS theory during the long term ageing. The morphology of primary and tertiary γ' phases changes little, and the secondary γ' phase is splitting at the early stage. No TCP phase is found in the supersolvs HTed alloys. The size and morphology variations of γ' phases in the supersolvs HTed alloys are smaller than those in the subsolvs HTed alloys, indicating that the former has the better microstructure stability.

The trusted computing technology SGX protects the confidentiality and integrity of key codes and data by isolating a trusted execution environment, which can help prevent all kinds of attacks. Firstly, the research background and working principle of SGX were introduced, the research status of SGX in the field of trusted computing were analyzed. Then, sorted out the current application difficulties and solutions of SGX were sorted out and compared with other trusted computing technologies. Finally, SGX technology development direction in the field of trusted computing was discussed.

In the industrial production process of traditionally fermented flour products, the influence of a certain storage period of fresh flour on the production process and product features of Chinese steamed bread(CSB) as fermented food is very prominent, and often causing quality fluctuations. In this paper, the lab-milled 3 flours were taken as 3 repeat samples set under the condition of room temperature, with the tools of dough rheo-fermentation instrument and other equipment. Regular analysis on rheo-fermentation and other properties of the dough, as well as the quality sensory evaluation of Chinese steamed bread (CSB) was conducted to determine a reasonable storage period for fresh wheat flour. The results showed that during the storage processes, the dough stability time increased and the weakening degree decreased, with the dough rheological property improved. The fermentation volume of rheo-fermentometer decreased significantly, so as the volume of the CSB. But the trend of change of the sensory evaluation characteristics of the CSB was not obvious. The test results by instrument Rheo F4 can reflect the rheo-fermentation properties of the dough,wherein rheo-fermentometer, such as the time required for maximum development (T1), maximum development reached by the dough (Hm), and dough development height at final fermentation time (h), have obvious guiding for production of the CSB. We therefore suggest that the flour to be used for the industrial production of CSB should stay in storage for more than 7 days after milling.

Synthetic Aperture Radar (SAR) has attracted much attention in the recent decades owing to its allweather and high-resolution working mode. As an active radar system, the high-resolution imaging process of SAR systems is affected by different types of strong, complex, and variable electromagnetic interferences that can severely affect the final high-resolution SAR imaging results. Thus, developing ways to effectively suppress complex electromagnetic interferences is a major challenge and focus of SAR detection. In this paper, we summarize the key elements and main concepts underlying interference suppression in high-resolution SAR imaging, including different interference patterns, interference sources, interference scattering mechanisms, radar antenna configurations, and target characteristics. We then consider the essential task of interference suppression algorithms. Recent papers that detail the representative SAR algorithms used to mitigate suppressed and deceptive jamming are introduced and summarized to provide references for future research.

BackgroundSynchrotron radiation experimental methods have unique advantages in studying the structure and physical properties of materials, but it is a challenge for many experimental methods to achieve synchrotron radiation in situ high temperature conditions, especially above 2 000 K. Laser heating methods can achieve rapid, micro-region extreme high temperature conditions, and have become an important tool for the study of high temperature physical properties.PurposeThis study aims to develop a portable laser heating device for Shanghai Synchrotron Radiation Facility (SSRF) in situ experiments in the field of extreme high temperature research, such as high entropy alloys, turbine blades, aviation materials, etc.MethodsA 100 W continuously tunable near-infrared fiber laser was used as the heating souce, the sample was heated up by laser through the focusing lens and generated thermal radiation. The radiation spectrum was collected through the spectral collection focusing lens and measured by spectrometers. The temperature gradient and temperature stability of the sample were fitted by the blackbody radiation method. Finally, the melting experiment of pure tungsten sheets in vacuum was conducted to verify its maximum heating temperature, and the temperature gradient and stability measurement of the device were calibrated with platinum samples.ResultsWe Experimental results show that melting point of about 3 695 K for tungsten sheets in vacuum is achieved using this device, and X-ray diffraction patterns of MoS2 and CTAB-MoS2 materials under 1 608 K in situ are obtained at the surface diffraction beamline station of SSRF.ConclusionsThe laser heating method developed expands the extreme experimental conditions in SSRF, and provides an important means to study high temperature physics for materials.

The service model of cloud computing creates a serious threat to user data security, the trustworthiness of cloud computing through third parties, must be evaluated then the healthy development of the cloud computing industry can be guaranteed. The research of the National High Technology Research and Development Program of China, “trusted platform for third-party cloud computing online evaluation and analysis technology” were summarized. The trusted evaluation model and architecture were described from the cloud platform, the dynamic evaluation technology, the credible evidence collection and the trusted test mechanism, the credibility of the quantitative evaluation method, and the prototype system integrated by tools , to evaluate the credibility of cloud platform.

This paper discusses anti-deceptive jamming methods based on single-channel and fixed waveform assumptions for synthetic aperture radar imaging. Using the essential defects of the deceptive-jamming theory, the information acquisition ability of the Synthetic Aperture Radar (SAR) system in a complicated electromagnetic environment is effectively improved with limited degrees of freedom in spatial and time domains. Geometric and signal models of SAR imaging and deceptive jamming are established and the different characteristics between them are analyzed according to their working mechanisms. Upon extracting their characteristic differences via different imaging processes and enhancing them based on statistical information, the degree of separation between the true and false targets is increased. Therefore, identification on the deceptive jamming is realized. Moreover, an approach for the dynamic synthetic aperture is used to formulate an optimization problem for the reconstruction of true and false targets. By solving such a problem, the true and false targets are separately reconstructed with super-resolution, achieving the goal of deceptive-jamming suppression. The effectiveness of the proposed methods is verified by simulations.

T4 link is the critical load-bearing component for nozzle element of a certain engine. Whether the nozzle load meets the requirements or not at high temperature is the key factor in the structural integrity of the nozzle unit. It’s analyzed that strain response of the T4 link was resulted from mechanical load, thermal gradient and material parameter using the thermo-solid coupling method. The T4 link load at high temperature was measured with the high temperature strain gauge on bed test. The process for bonding and assembling the high temperature strain gauge was developed. the equation extension method of the load calibration was deduced, the measurement method containing load calibration, thermal correction, and date processing for the high temperature load were established. The aero-engine bed test shows that the variation tendency and value of the thermal-output strains vary much between T4 links. The maximum error for T4 link is 0.27 kN, the maximum measured tension is 62.1% of the designed load value, the maximum pressure is 58.46% of the designed load value, and the structural strength design of T4 link meets the operating requirements.

This paper proposes a 1-bit Synthetic Aperture Radar (SAR) imaging method based on a singlefrequency time-varying threshold. Synthetic aperture radar echoes are quantized to 1-bit sampling data by comparing the data with the threshold; this reduces the data-width of the SAR echoes, consequently simplifying the system and improving efficiency. The conventional 1-bit sampling compares the signal to a zero threshold, bringing nonlinear distortion to the relative amplitude and degrading the imaging quality. The random threshold can keep the amplitude information, but it introduces additional noise-like interferences. In contrary, the single-frequency time-varying threshold can maintain the amplitude information lost during the 1-bit sampling and quantization, and at the same time, eliminate noise-like interferences; thus, the imaging quality of SAR using 1-bit sampling and quantization can be improved. The focusing quality and the amplitudemaintaining ability of the proposed approach is quantitatively analyzed, and the effectiveness of the approach is verified by an imaging experiment on a scene.

The paper presents the domestic and overseas current status of the steel applied to aircraft landing gear in combination of the design concept and requirements for aircraft landing gear. The application features and concept of the steel used for landing gear are summarized and the domestic and overseas status are compared. For the moment, the low-alloy ultra-high strength steel and high-alloy ultra-high strength steel are all being used in the material system for aircraft landing gear steel, and the complete technical system for its anti-fatigue manufacturing is built. At present, China's development and application of high strength steel applied to aircraft landing gear is at the world advanced level. At last, the prospect for future development is analyzed.

In this paper，ZnFeZ OQ and Zn0/ZnFeZ OQ were synthesized by precipitation method. The structure and appearance of the synthesized nanoparticles were characterized by XRD and SEM. The results show that ZnFeZ OQ and Zn0/ZnFeZ OQ can be successfully prepared by XRD;we can find that the ZnFeZ04 is irregular, and the Zn0/ZnFeZ OQ is the ball type and the small particles are attached. A study on the photocatalytic performance of the simulated wastewater(Methylene blue)with Zn0/ZnFeZ OQ under the simulated sunlight showed that the highest degradation rate could reach to 89.2%.

By using the finite element software ABAQUS,the finite element model of large diaphragm-rubber coupling is established,and the simulation and analysis of its static stiffness is carried out,the static torsional stiffness,radial and axial stiffness of the diaphragm- rubber coupling are calculated. Finally,through the establishment of the coupling stiffness calculation model,the calculation method of the contribution amount of couplings rubber block coupling components and the diaphragm components to radial and axial stiffness is proposed,the guidance for further study of the coupling design is provided.

On the basis of a large number of reference,the research trends on modification of cycloidal gear,the accuracy control of cycloidal gear transmission and the dynamics of RV reducer is introduced,and the analysis and discussion on the key technology of the modification,manufacturing and manufacturing equipment development need to be solved of the cyclonical-pinwheel transmission is carried out.

Aiming at the cycloidal gear used in RV reducer of robots,based on the concept of the single tooth without side clearance,the tooth surface equation of the cycloidal gear after modification is deduced by directly adding the second- order parabolic modification amount to the theoretical conjugate tooth profile along the normal direction. The modification amount of different meshing position on tooth profile curve could be flexibly controlled by controlling the tooth profile modification coefficient. The differences between the parabolic modification and the traditional modification method of the combination of isometric and travel distance,the proposed parabolic modification method is much closer to the complete conjugate tooth profile on the main meshing areas.The TCA program of cycloidal- pinwheel transmission which is written in Matlab formed parabolic transmission errors and the correctness of this modification is proved,which provides a new thought for the modification design of cycloidal gear used in RV reducer.

For the problem that the finite element simulation analysis of temperature field of large rubber coupling of ships is difficult to convergence because of the large load,the large deformation of rubber piece parts and the nonlinear characteristics of rubber materials,by using the decoupling method,combined with the node equivalence method,the finite element mathematical mode of the rubber material thermal analysis is established theoretically. With some kind of diaphragm rubber couplings as an example,the thermal of its rubber element is analyzed,the steady temperature distribution and transient temperature field curve are got. Studying of the results by using least square method,finds that the relationship of the maximum temperature rise with load torque is a parabola,and the relationship of the maximum temperature rise with load with load frequency is a linear. The simulation results and the experimental results that obtained through torsion test have a good consistency. The feasibility of this approach is proved,and it has the guiding significance for the actual work.

The background values of chemical elements in stream sediments are an indispensable tool in geochemical prospecting work, and they are of important significance for regional geochemical anomalies assessment. However, there is a lack of poly-elements background values in Tibet, which are based on the surface material from the micro landscape area thereby limiting understanding of the existing stream sediment anomalies to a certain extent. Analysis of the chemical elements background values and distribution characteristics of 69 kinds of elements in 2800 stream sediment combination samples covering about 12000 km2 in Yangbajain-Qinglong area have been conducted and are reported in this paper. From north to south, the area is divided into three geochemical divisions of Bangor-Basu, Longer-Nanmulin and Lhasa-Zayu. The results indicate that content of SiO2 (68.6%-77.0%) in the study area is higher compared to the average value of stream sediments nationwide. The high content of SiO2 is related to strong weathering and occurrence of large-scale intermediate-acid intrusive rocks in the study area. While other elements are lower and differentiated in three geochemical divisions. Bangor-Basu division is characterized by enrichment of Li, Sr, B, N and Cl which are related to high-temperature hydrothermal or gas-liquid. Longer-Nanmulin division is enriched with iron group elements, rare element (Zr) and rare earth element (Sc). Lhasa-Zayu division is enriched with petrogenetic elements, light rare earth elements, rare elements, dispersed elements and chalcophile metallogenic elements. The differences in element content distribution are closely related with the stratum, rock mass, deposits and mineralization in the geochemical divisions. This study gives the background values for 69 kinds of elements in the Yangbajin-Qinglong area, such as the chalcophile metallogenic elements of Au, Ag, Cu, Pb and Zn with 0.26 ng/g, 41 ng/g, 4.04 μg/g, 25.2 μg/g and 25.6 μg/g, respectively. These data fill a vacancy in the chemical elements background values on the micro-landscape areas of Tibet, and provide references for regional exploration study and geological prospecting work in Yangbajain-Qinglong and adjacent areas.

An enterprise architecture for safety production management of coal mine was built, a business architecture framework was given that included business lines, business components, normal business processes and organization architecture. Steps to build data architecture from business processes, data-driven application architecture defining mode and technology architecture reflecting characteristics of coal mine information were introduced. Finally, a method of building enterprise architecture for safety production management of coal mine with integrated enterprise modeling software was introduced briefly.

Aiming at the problem that the existing trusted container framework lacks key protection, a trusted container hierarchical key management (TCKM) method based on the trusted platform module is proposed. The hardware TPM and the container key block are bound by the hierarchical key management mechanism to protect the security of the generation and storage stage of the container key block. When the key is used, the container attribute is verified through the key authorization value, so that only the specified container that meets certain attributes can obtain and use the key, preventing the theft of the container key block, and realizing the secure use of the key. Finally, the encryption method combining kernel and hardware TPM is adopted to improve the efficiency of data protection based on TCKM key management method. The TCKM key management method is implemented and evaluated based on Docker18.09. The results show that the mechanism can effectively protect the security of the key and the confidentiality of the file data in the container. [ABSTRACT FROM AUTHOR]

Garlic products are rich in nutrition and possess antibacteria, anti-inflammatory, antioxidant, anti-tumor, and the ability to lower blood sugar and lipids, as well as improve animals' appetite. Garlic products can improve the production performance and product quality of animals, and enhance the immunity. The paper summarizes the function of garlic products and their application in animal production, and summarizes and discusses the problems existing in the application of garlic products in animal production, in order to continuously improve the function and value of garlic products, and provide reference for the continuous promotion and application of garlic products in animal production. [ABSTRACT FROM AUTHOR]

It is of great practical significance to study the molecular basis of plant response to low temperature stress and breed new varieties of cold-tolerant for ensuring food security. However, the study is relatively scarce about cold resistance of foxtail millet (Setaria italica). To further explore the molecular mechanism of millet responsing to low temperature stress at seedling, 33 RNA-Seq data of foxtail millet at different development stages and different cold stress times were used. Gene expression matrix was constructed using 32 017 highly expressed genes. WGCNA package of R software was used to construct a co-expression network, which was further divided into 44 modules. The genes related to cold stress of foxtail millet were existed in several modules. Here, 3 modules with most cold stress genes were selected for GO enrichment analysis to annotate the function of target genes, and it was found that most candidate genes were related to abiotic stress responses. Above results provided new ideas for stress resistance of foxtail millet, and the key genes of cold stress provided effective resources for breeding the new variety of cold tolerance in foxtail millet. [ABSTRACT FROM AUTHOR]

A simultaneous partial nitrification, anammox and denitrification(SNAD) micro-aerobic system was constructed. The effects of different particle sizes of ZVI on the micro-aerobic system were investigated from the aspects of operation, microbial performance and community structure by adding 120 mg of zero-valent iron(ZVI) into the system. The results showed that the TIN removal rate of the system stabilized at 83.591% and the electron transport system activity(ETSA) was 1.48 times of the inoculated sludge under the domestication of ZVI with a partical size of 50 nm (50 nZVI), which was higher than the influence of other particle sizes of ZVI. The smaller the particle size, the more production of extracellular polymers promoted by ZVI, the more stable of the activated sludge structure. This was due to the fact that ZVI of smaller particle size was more easily adsorbed and utilized by microorganisms. The results of microbial community analysis showed that the smaller the particle size, the higher the diversity of the microbial community mediated by ZVI, and the more complex the community structure. ZVI mediation promoted the enrichment of microorganisms that were not sensitive to oxygen demand. Candidatus_Brocadia and Candidatus_Kuenenia, two kinds of AnAOB were the main bacteria detected in the samples with the highest abundance of 4.650% and 0.692% under the influence of 50 nZVI. Under nZVI, AnAOB acted together with two facultatively anaerobic denitrifying bacteria, Gemmobacter and norank_f_Comamonadaceae, which constituted the denitrification pathway of SNAD. In contrast, facultatively anaerobic denitrification was the main denitrification pathway mediated by mZVI.

How the government scientifically forms the top management team greatly influences the performance of water conservancy project, which is a concern for practitioners and scholars. According to the investigation in many cases, the current top management team formation methods of water conservancy projects can be classified into nine categories. Through theoretical analysis and literature review, it is found that six factors influence the selection of the top management team formation methods in water conservancy projects. On this basis, a relationship matrix of top management team formation methods and influencing factors is developed, and the top management team formation method with the help of the 'entropy weight-VIKOR method' is optimized. [ABSTRACT FROM AUTHOR]

In order to make full use of the railway communication dynamic detection data and reasonably evaluate the quality of GSM-R network, 13 specific parameters for quantitative description are selected from four types of detection items, including handover, voice call, voice quality and CSD data transmission according to the application requirements of CTCS-2 and CTCS-3 lines for GSM-R network, and each parameter is evaluated separately based on corresponding standard specifications and data characteristics. Then, the fuzzy analytic hierarchy process based on peer consensus model is used to calculate the weight of each parameter. Finally, comprehensive evaluation method and GSM-R network quality comprehensive evaluation index (GQI) are proposed based on dynamic detection items and detection problems. By selecting actual dynamic detection data and calculating GQI, the influence of detection parameter's changes on the evaluation results is discussed, and the correlations between different network states of GSM-R railway lines and evaluation results are analyzed. The results show that GQI can not only evaluate the whole GSM-R network quality of railway lines, but also quantitatively evaluate the four types of detection items separately, which provides support for trend analysis of GSM-R network state and management of railway GSM-R wireless network. [ABSTRACT FROM AUTHOR]

To address the phenomenon that ultrasonic-assisted machining might improve the microstructural properties of high-strength aluminum alloy surfaces by forming micro-scoring surfaces on the workpiece surfaces, an experimental study on the microstructure of surfaces milled by single- excitation rotary ultrasonic longitudinal torsion composite milling was conducted: the effects of machining parameters on the water contact angle were analyzed based on the water contact angle theory and the kinematic theory of longitudinal torsion milling; secondly, a single-excitation ultrasonic longitudinal torsion milling test platform was built, and the orthogonal method was used to study the effects of different machining parameters on the surface roughness, milling forces and surface wetting performances. The results show that the surface quality is best when the ultrasonic amplitude is as 4 µm, and the cutting speed and feed are positively correlated with the surface roughness and water contact angle; the surface water contact angle under ultrasonic machining mode is larger than that of the normal mode, and the surface water contact angle machined by low amplitude is larger than that of high amplitude during ultrasonic machining. And the differences between the surface water contact angle machined by high amplitude and low amplitude are not significant when the speed reaches a certain amount. Suitable machining parameters under the ultrasonic longitudinal revise processing method may reduce the roughness of the machined surfaces and change the wettability of the surfaces. [ABSTRACT FROM AUTHOR]

Volcanic hazard evaluation and zonation, as the effective countermeasures, plays an important role in volcanic emergency response and hazard mitigation. Taking Changbaishang volcano as an example, this paper reviews on the study history of volcanic hazard zonation in China. The major types of volcanic hazards in China, which are potentially related with the active volcanoes, involve tephra fallout, pyroclastic flow, lava flow and lahar. The volcanic zoning maps of Changbaishan volcano compiled in 2000 and 2012 respectively show the progresses in volcanic hazard assessment and hazard zonation of China. It is proposed that the probabilistic method such as event tree should be applied in compiling the volcanic hazard map of China in future, which represents the most-up-to-date technical trend in volcanic hazard zonation in the world. [ABSTRACT FROM AUTHOR]

Oncogenic mutations are responsible for a majority of the malignancy of melanoma. Activating mutations of NRAS gene are found in 15%-20% melanoma cases, endowing the tumor cells with more aggressive phenotypes and greater difficulty to treat. The development of targeted inhibitor of mutant NRAS remains a big challenge since the mutation sites could hardly be druggable. Therefore, immune checkpoint inhibitors are currently recommended as the first-line therapy for NRAS mutant advanced melanoma albeit the response rate is still far from satisfaction. In recent years, the exploration of targeted therapy regimens has focused on the downstream pathway of NRAS, the mitogen-activated protein kinase (MAPK) pathway. A novel MEK1/2 inhibitor tunlametinib was reported to achieve an objective response rate (ORR) of 34.7% which is higher than the ORR of binimetinib in previous report. However, the phase Ⅰ trial of the pan-RAF inhibitor belvarafenib and the ERK inhibitor ulixertinib failed to show marked benefits. In the meanwhile, MEK inhibitor-based combination therapy has also achieved some progress: it was reported in the phase Ⅰb trial of the selective BRAF/CRAF inhibitor naporafenib (LXH254) combined with Trametinib in NRAS mutant melanoma that the ORR was 46.7%. The ORR of binetinib plus the cyclin-dependent kinase 4/6 (CDK4/6) inhibitor, ribociclib, was 32.5% in patients with NRAS mutation with concurrent alterations of CDKN2A, CDK4, or CCND1. The response rate of the combination of focal adhesion kinase (FAK) inhibitor, IN10018, and cobimetinib was 38.5%. On the other hand, only 27.2% of patients carrying NRAS mutation responded partially to the combined regimen of immune checkpoint inhibitor programmed death ligand-1 (PD-L1) monoclonal antibody durvalumab+trametinib. In addition, some preclinical findings have also shown translational potentials: for example, heat shock protein 90 (HSP90) inhibitor XL888 and serine/threonine protein kinase 19 (STK19) inhibitors were found to inhibit the growth of NRAS mutant melanoma in animal models. This article reviewed the oncogenic roles of NRAS mutation in melanoma and the cutting-edge clinical trials for the treatment of NRAS mutant melanoma, aiming to provide alterative treatment options for clinical practice and inspire novel combination regimen.

[Objective] The spatiotemporal characteristics of soil erosion were analyzed in order to provide a reference for soil erosion control and evaluation of soil and water conservation benefits. [Methods] Based on the RUSLE soil erosion equation, the spatial-temporal evolution of soil erosion in the typical black soil region of Binxian County, Heilongjiang Province from 2000 to 2020 was analyzed with the support of RS and GIS. The effects of topographic factors and land use on soil erosion were also investigated. [Results] ① The average modulus of soil erosion in 2000, 2010, and 2020 was 893.02 t/(km2·yr), 499.84 t/(km2·yr), and 1 561.02 t/(km2·yr), respectively. The soil erosion intensity was mainly classified as slight and mild. ② The low intensity erosion was distributed across the entire region, and the high intensity erosion was mainly located in the southern mountainous area. ③ Erosion mainly occurred at elevations of 100 to 200 m. Soil erosion area was inversely proportional to slope. 0°—5° slope was the main erosion gradient zone. Soil erosion area in the direction of the north slope was larger than in the direction of the south slope; ④ The soil erosion modulus and the area of sloping farmland in the study area were larger. This area is the key area for soil erosion control in Binxian County, Heilongjiang Province. [Conclusion] From 2000 to 2020, the average soil erosion modulus initially increased and then decreased, showing a significant spatiotemporal differentiation. Topographic factors and land use change had significant driving effects on soil erosion in the study area. It can be used as a reference for soil erosion control and soil and water conservation benefit evaluation in black soil region.

The in-situ monitoring technology for overburden movement in mining has the features of adapting to complex geological conditions in deep shaft high pressure water and thick coal seam mining, multi layer dynamic monitoring, and high-precision remote real-time online transmission. It provides effective data support for mining enterprises to carry out roof disaster prevention and control. Starting from the practical background of coal mining application, this paper systematically reviews the development process, technological progress, and application effects of in-situ monitoring technology for overburden movement in mining. Based on the development history of mining pressure theory and overburden movement monitoring technology in China, this paper comprehensively introduces the important stages of in-situ monitoring technology for overburden movement in mining. It elaborates on the theoretical innovation and technological breakthroughs achieved by this technology in three aspects: multidimensional real-time collaborative monitoring, unmanned online monitoring, and deep rock movement monitoring. Based on the monitoring engineering examples of coal mines such as Bulianta Coal Mine, Tongxin Coal Mine, and Gaojiabao Coal Mine, the effectiveness of in-situ monitoring technology for overburden movement in mining is demonstrated in practical engineering applications. The application prospects of this technology in different types of mining areas and research fields are discussed. It is pointed out that the development trend of in-situ monitoring technology for overburden movement in mining is precision, intelligence, and integration, namely optimizing sensor performance and layout plans to improve monitoring precision and accuracy, using artificial intelligence, big data, and Internet of things technology to achieve automatic analysis and prediction, combining the in-situ monitoring technology with other technologies to form a complete monitoring system.

To study the fabrication processes of micro-texture for the elliptical vibration assisted turning technique and the characteristics of machined micro-surfaces, the change rules of surface microtexture was analyzed with vibration principle of ellipse and the micro-texture formation under different speeds and feed rates. The vibration track, surface topography, single micro-texture geometry size and surface roughness were analyzed under the elliptic vibration track measurement tests and eliptic vibration turning tests. The analyses results show that in the turning test processes, compared to the common turning, due to the space elliptic movement of the tool, the surface of ultrasonic elliptical vibration turning presents micro-texture grooves similar to ellipse. With the changes of rotation speed and feed rate, it indicates that the geometric size, profile height and surface roughness of micro-texture grooves will change regularly based on the theoretical analyses and experimental results. [ABSTRACT FROM AUTHOR]