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AIM: To investigate the structural changes in anterior segment of cataract patients after phacoemulsification combined with intraocular lens(Phaco+IOL)implantation, and to analyze theirs correlation.METHODS: Retrospective case study. A total of 44 cases(88 eyes)of cataract patients who underwent Phaco+IOL surgery at ophthalmology department of the Peking University Third Hospital from January 2018 to December 2022 and consented to pre- and postoperative ultrasound biomicroscopy(UBM)were included. Patients' sex, age, axial length, corneal curvature, and IOL parameters were collected. UBM was utilized to measure various anterior segment parameters pre- and post-surgery, including anterior chamber depth(ACD), scleral ciliary process angle(SCPA), iris-lens contact distance(ILCD), maximum ciliary body thickness(CBTmax), and ciliary body thickness at 0 mm from the scleral spur(CBT0). The posterior chamber area(PCA)was calculated using Image J software.RESULTS: Significant increases in ACD 3.50(2.89, 3.68)mm, CBTmax 1.199±0.233 mm, CBT0 1.11(0.964, 1.23)mm, and PCA 1.21(0.926, 1.57)mm2 were identified postoperatively compared with preoperative values(all P

Fatty acids in oat flour have been analyzed by using multiple reaction monitoring mode of gas chromatograph-mass spectrometer. The samples and fatty acid standards were methylated by potassium hydroxide - methanol and boron trifluoride- methanol solutions for 15 min to produce the corresponding fatty acid methyl ester. Then, the products would be separated through DB-FastFAME (90 m×0.25 mm×0.25 μm) capillary column. Multiple reaction monitoring mode (MRM) was performed under electron bombardment ionization (EI) source, and the external standard method was carried out for quantitative analysis. 40 kinds of fatty acid methyl esters could be completely separated within 38 min. A good linear relationship was achieved in the concentration range of 0.4~40 μg/mL. The correlation coefficients of standard curve were all greater than 0.999 7. The limit of quantification of 6 fatty acids such as C20:2 was 0.003 g/100 g, and the remaining 34 fatty acids was 0.000 6 g/100 g. The standard recoveries of fatty acids were 86.6%~107.3%, and the precision was between 0.9% and 5.2%. It is a method for simple operate and high selectivity, which has a good accurate, precise and sensitive. The method is suitable for the rapid and accurate determination of fatty acids in oat flour.

Lactic acid bacteria (LAB) plays an important role in the production of sourdough, and has a significant impact on its flavor and other qualities. In order to select LAB starter culture for specialty sourdough and develop differentiated sour dough bread, this study evaluated the glucose metabolism capacity, organic acid production capacity and flavor characteristics of LAB strains isolated from different kinds of traditional fermented foods, and their effects on the flavor of sourdough and bread were also verified. The results showed that there were 6 LAB strains with strong glucose metabolism and acid production performance, and excellent flavor characteristics. The volatile flavor substances produced by these strains were mainly composed of alcohols, esters, ketones, aldehydes, acids, and other compounds. Among them, two Lactobacillus plantarum strains might be the main contributors of special flavors such as sourness, fruitiness and rice wine flavor to sourdough bread. These obtained strains provide resources for the development of sourdough starter culture with characteristic aroma components, and have potential for industrial application.

Background: Diabetic cardiovascular complications are the leading cause of diabetes-related deaths. These complications place an enormous and growing burden on global health systems and economies. The objective of this study was to conduct a systematic review on the therapeutic mechanisms of Taohe Chengqi Decoction (THCQD) in the treatment of diabetic cardiovascular complications. To predict the potential mechanisms of action of THCQD on diabetic cardiovascular complications using network pharmacology, and to validate these predictions through molecular docking analysis. Methods: To collect relevant animal experiments, we searched a total of 6 databases. Eligibility for the study was determined based on inclusion and exclusion criteria. Data extraction was then performed on the literature. Methodological quality of animal studies was assessed using SYRCLE criteria. Based on network pharmacology, intersecting genes for THCQD and diabetic cardiovascular complications were obtained using Venny, PPI analysis and topology analysis of intersecting genes were performed; GO and KEGG were used for enrichment analysis and prediction of new targets of action. Molecular docking techniques were employed to model the interactions between drug components and target genes, thereby validating the results of network pharmacology predictions. Results: A total of 16 studies were finally identified that fit the direction of this review. Included 6 studies of the myocardium, 1 study of the aortic arch, 5 studies of the femoral artery, 4 studies of the thoracic aorta. THCQD exhibited anti-inflammatory, anti-fibrotic and anti-atherosclerotic effects on cardiovascular complications in diabetic rats. Network pharmacology results showed that C0363 (Resveratrol), C0041 (Emodin), and C1114 (Baicalein) were the key components in the treatment of diabetic cardiovascular complications by THCQD. PPI results showed that INS, AKT1, TNF, ALB, IL6, IL1B as the genes that interact with the top 6. KEGG enrichment analysis identified the AGE-RAGE signaling pathway in diabetic complications as the most prominent pathway enriched by THCQD for diabetic cardiovascular complications genes. The results of molecular docking showed that the key active components demonstrated favorable interactions with their corresponding target genes. Conclusion: In conclusion, the results of both basic and web-based pharmacological studies support the beneficial effects of the natural herbal formulation THCQD on diabetic cardiovascular complications. This decoction has anti-inflammatory and antifibrotic properties and is effective in ameliorating diabetic cardiovascular disease. The network pharmacology results further support these ideas and identify the AGE-RAGE signaling pathway in diabetic complications as possibly the most relevant pathway for THCQD in the treatment of diabetic cardiovascular complications. The extent of the therapeutic potential of all-natural herbal components in the treatment of diabetic cardiovascular disease merits further investigation.

C20H40Cl2CuKO10, triclinic, P1‾$P\overline{1}$ (no. 2), a = 9.0148(5) Å, b = 9.3066(5) Å, c = 17.7296(10) Å, α = 78.383(2)°$78.383(2){}^{\circ}$, β = 88.488(2)°$88.488(2){}^{\circ}$, γ = 72.982(2)°$72.982(2){}^{\circ}$, V = 1392.35(13) Å3, Z = 2, Rgt(F) = 0.0781, wRref(F2) = 0.2089, T = 170(2) K.

Does administrative reform boost the favorable business environment? What is the mechanism underlying such reform? This study explores the relationship between administrative reform and the business environment in China via a mixed-method approach. This paper extends administrative burden theory to government-company interactions and then proposes a framework that bridges administrative reform and the business environment. Based on firm-level survey data and case data, this quantitative analysis confirms that administrative reform can significantly boost the favorable business environment and that administrative burden is a mediating variable during this process. The qualitative comparative analysis contends that there are three different configurations that can boost the favorable business environment: collaborative governance, government-driven, and enterprise-driven configurations. Theoretically, this paper extends the administrative burden theory, which brings companies into this theory as new actors. We also provide reform advice for practitioners.

Objective： This study aimed to explore the fatigue relieving effect of Lonicera caerulea Berry polyphenol, hawthorn polyphenol microcapsules, lactoferrin and vitamin C as polyphenol compound formula to alleviate fatigue. Methods： The commercial sports nutrition food with the compound formula of creatine, β-hydroxy-β-methylbutyrate, fructose diphosphate, taurine, vitamin B6 and watermelon powder was used as the positive control. The experiment of exhaustive swimming in mice was carried out. The fatigue related indexes were determined by the kit, and the microscopic pathological tissues of the organs were observed by H&E staining. Results： There was no significant difference in body weight of mice (P＞0.05). Compared with the normal group, no significant difference in organ index in the dietary supplement group (P＞0.05) was found. Polyphenol compound formula significantly prolonged the swimming time of mice at room temperature and low temperature by 106.01% and 140.94%, respectively (P＜0.01). Moreover, oxidative stress, metabolite accumulation and energy metabolism, and down-regulated secretion of inflammatory factors (P＜0.01 or P＜0.05) were also improved. It promoted the cell nucleus increase in muscle, inflammatory cell infiltration in the liver, and redness and shedding of tubular epithelial cells in the kidney. Conclusion： Polyphenol compound formula can relieve exercise fatigue at low temperature and room temperature.

C18H15ClN2O2S·C8H6O4, triclinic, P 1‾ $\overline{1}$ (no. 2), a = 8.4340(17) Å, b = 12.172(2) Å, c = 12.816(3) Å, α = 89.98(3)° $89.98(3){}^{\circ}$ , β = 77.41(3)° $77.41(3){}^{\circ}$ , γ = 72.52(3)° $72.52(3){}^{\circ}$ , V = 1221.7(5) Å3, Z = 2, R gt(F) = 0.0482, wR ref(F 2) = 0.1344, T = 293 K.

C80H38Er2F16N8O18, triclinic, P1‾ $P\overline{1}$ (no. 2), a = 11.4228(4) Å, b = 12.6712(3) Å, c = 13.2663(4) Å, α = 102.660(2)°, β = 98.047(3)°, γ = 105.509(3)°, V = 1764.54(10) Å3, Z = 1, R gt(F) = 0.0311, wR ref(F 2) = 0.0668, T = 293(2) K.

In severe operating conditions of spent fuel reprocessing plants, such as strong acid and high temperature, equipment corrosion problems are common. The corrosion problems/incidents in Japanese reprocessing plants and some relevant experimental research, evaluation and investigation work carried out by Japanese institutions and scholars were summarized in this paper. The related research results and experience from Japan will provide our country with some reference and technical basis for the design and manufacture, life prediction, preventive maintenance of key equipment, periodic safety evaluation of reprocessing facilities, etc.

Objective To investigate the relationship between solid pulmonary nodules with maximum diameter≤2 cm and the bronchi in order to provide more valuable clues to differentiate benign and malignant solid pulmonary nodules. Methods The clinical and CT data of 776 patients with solid pulmonary nodule at a maximum diameter of not larger than 2 cm confirmed by pathology in our hospital from January 2014 to January 2021 were analyzed retrospectively. According to pathological types, the patients were divided into malignant nodule group(n=340) and benign nodule group(n=436), and those with benign nodules were further assigned into inflammatory nodule subgroup(n=299) and benign tumor subgroup(n=137). Bronchogram sign on CT images were classified into 4 types according to the relationship between pulmonary nodules and bronchi. The incidence and types of different bronchogram sign on CT images were compared between malignant nodule group and benign nodule group, and between inflammatory nodule subgroup and benign tumor subgroup. The diagnostic performance of bronchogram sign on CT images to differentiate benign and malignant solid pulmonary nodules was evaluated. Results ① The incidence of bronchogram sign on CT images was higher in the malignant nodule group than the benign nodule group(65.9% vs 31.4%, P < 0.001). Types Ⅰ and Ⅱ signs were more common in the benign nodule group, while Types Ⅲ and Ⅳ signs were more common in the malignant nodule group(all P < 0.01). The sensitivity, specificity, and accuracy of bronchogram sign on CT images was 82.1%, 56.2%, and 72.3%, respectively in differentiation of benign and malignant solid pulmonary nodules. ②The incidence of bronchogram sign on CT images was statistically higher in the inflammatory nodule subgroup than the benign tumor subgroup(39.1% vs 14.6%, P < 0.001). Type Ⅳ was more common in inflammatory nodule subgroup(P < 0.05). However, no significant differences were observed in the other 3 types between the 2 subgroups (all P > 0.05). Conclusion Bronchogram sign on CT images is valuable in differentiation of benign and malignant solid pulmonary nodules measuring ≤2 cm in diameter. Irregular air bronchogram sign or truncation of bronchus in the margin of nodule is highly suggestive of malignancy.

Nowadays, with the continuous understanding of the pathogenic mechanism of bacterium, the demand for antibacterial plastic products had significantly increased. Besides that, many counties issued mandatory standards for plastic products, which imposed strict requirements on ash content to prevent the addition of excessive inorganic matter to plastics in order to avoid weakening the properties of plastics and deteriorating the recyclable property. Based on this, the development of composites with organic fiber-loaded antibacterial agents is of practicable value and urgency. We used an open-ring addition reaction to modified aramid fiber (AF) by utilizing epoxypropyltrimethoxysilane to react with the reactive groups on the surface of AFs. Subsequently, the modified fibers were surface loaded with silver ionic glass beads. After that, a series of high-density polyethylene composites with excellent mechanical properties and antibacterial properties were prepared using melt mixing method. It was shown that the composite had a low ash value (1.88 wt%) even at a higher filling concentration (7 wt%) and the fibers could change the crystalline properties and morphology of the composite. Because of the fiber reinforcement and crystallization induction effects, the tensile strength and elasticity module of the composites could be improved by 141% and 136%, respectively. In addition, the composites had excellent long-lasting contact antibacterial effects against the inhibition of E. coli. The proposed organic fiber loading technique and antibacterial composites will provide a method for designing and preparing eco-friendly and high-performance plastic products.

Studying the seed trait–stem trait–individual spatial pattern system is helpful for understanding the developmental direction of plant dynamics and populations under grazing disturbance as well as the antagonistic relationship between animals and plants, but few systematic analyses of this spatial pattern system have been carried out. Kobresia humilis is the dominant species in alpine grasslands. We studied K. humilis seed traits and their relationship with K. humilis reproductive individuals, the relationship between reproductive and vegetative stems, and the weights and spatial patterns of reproductive and nonreproductive individuals under four grazing treatments: no grazing (control), light grazing, moderate grazing and heavy grazing. We explored the relationship among seed size and seed number with reproductive stems and vegetative stems along the grazing gradient and assessed the spatial pattern changes between reproductive and nonreproductive individuals. The results showed the following: (1) Seed size increased with increasing grazing intensity, and the coefficient of variation for seed size and seed number in the heavy grazing treatment was greater than 0.6. (2) The structural equation model showed that grazing treatment had a positive effect on seed number, seed size and reproductive stem number and a negative effect on reproductive stem weight. (3) Grazing treatment did not affect the resource allocation to reproductive stems and vegetative stems per unit length of reproductive K. humilis individuals. (4) Compared with the number of reproductive individuals in the no grazing treatment, the number in the heavy grazing treatment decreased significantly, and the negative correlation between reproductive individuals and nonreproductive individuals changed from a full-scale negative correlation to a small-scale negative correlation and a large-scale positive correlation. Our study showed that grazing could activate and change the resource allocation pattern of dominant species in a grassland and have significant positive effects on reproductive stem number, reproductive stem weight, seed number and seed size. Along a grazing intensity gradient, with the increase in distance between reproductive and nonreproductive individuals, the transformation of intraspecific relationships from a negative correlation to a positive correlation is an ecological strategy conducive to population survival.

Aileron stiffness simulator is a device to simulate the support stiffness of aileron actuator,which is a key device in airplane ground test. The research on the stiffness simulator is beneficial to its design and application,and has important engineering value. In this research,in order to establish the mechanical model accurately,the stiffness reduction factor is proposed. And the correctness of the mechanical model and simulation is verified through the stiffness test. Lastly,the thickness of the simulator is optimized based on the sensitivity of the target stiffness with distance. The results show that the stiffness reduction factor can be used to quickly predict the stiffness,and 7 mm is the optimal stiffness plate thickness of the simulator.

Objective To investigate the effect of ADAM17 on proliferation of cervical cancer cells in vitro and its mechanism. Methods The specific shRNA against ADAM17 was transfected into HeLa cells. Western blot and RT-qPCR were used to examine the interference efficiency. The relative rates of proliferation were determined by CCK-8 assay. The migration and invasion were evaluated by scratch test and Transwell test.Western blot was used to detect the protein expression of PCNA, EGFR, p-EGFR, ERK and p-ERK in each group. Results The expression of ADAM17 mRNA and protein were decreased in HeLa cells transfected by sh-ADAM17(P＜0.05).ADAM17 had no effect on migration and invasion of cervical cancer cells,but ADAM17 interference significantly inhibited the proliferation of cervical cancer HeLa cells(P＜0.05). The expression of PCNA, p-EGFR and p-ERK protein was down-regulated(P＜0.05). Conclusions Interfering with ADAM17 can inhibit the proliferation of human cervical cancer cell line HeLa, which may be related to EGFR/ERK signaling pathway.

Multi-line lasers were applied to the on-line defect detection for steel rails instead of single-line laser,which solved the problem of "pseudo defects" due to the vibration of rails under the mode of single-line laser. Images of multi-line lasers captured by camera were processed to realize the online detection and the accurate defect feature area was acquired with steps of the extraction of strip centers,detection of difference algorithm,discrimination between real and pseudo defects,image mosaic,etc. Images of the defect area were extracted by the cross-correlation and self-correlation information of laser curves,and there was no need for the step of depth mapping under the single-line mode,so the problem of "fault detection" caused by the vibration of rails was solved fundamentally. The technique is applied to on-line detection of defects for the bottom side of steel rails,and the detection rate is much higher than manual detection.

W18O49/C-TiO2 direct Z-scheme photocatalyst was prepared by a simple hydrothermal method. The structure, morphology, transport properties of photogenerated carriers and energy band structure were characterized by XRD, SEM, TEM, HRTEM, PL and other measurements. Under simulated sunlight illumination, the photocatalytic water splitting performance for hydrogen (H2) production and quantum efficiency were studied without adding any sacrificial agent. The results show that the construction of W18O49/C-TiO2 direct Z-scheme photocatalyst can significantly improve light absorption, accelerate the separation and transport of photogenerated carriers, and enable more photogenerated electrons participate in the photocatalytic reduction reaction, so the sample possesses high efficient photocatalytic activity. The photocatalytic H2 production tests show that under simulated sunlight illumination, the W18O49/C-TiO2 direct Z-scheme heterojunction can achieve H2 production rate of 209 μmol·h-1·g-1 without adding any sacrificial agents. It also exhibits strong photocatalytic stability; the H2 production remains unchanged during the 24 h cycle test.

A new application of baking soda was developed, the synthetic colorant in cereal was extracted by adding with methanol solution in this paper.To develop new uses of edible bicarbonate,synthetic colorants were extracted from cereals by adding methanol water solution of edible bicarbonate in this paper, Ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS)was used to test standard recovery.The extraction effect of edible bicarbonate of soda on five synthetic colorants of sunset yellow, amaranth red, carmine red, alluvium red and bright blue in cereals was investigated.The sample was extracted with 70 mL 40% methanol water vortexed with 1g edible baking soda, purified with Strata X-AW SPE column and determined.The results showed that, a good linearity was observed between 0.1 and 1.4μg/mL, and for the 5 synthetic colorants, the limit of detection was between 0.07 and 0.50 μg/g.The recoveries of the 5 synthetic colorants of different food substrates at different spiked levels (1, 2 and 10 μg/g) were all found to be in the recovery range specified in GB/T27404.The recoveries for the 5 synthetic colorants were found between 80.0% and 110% with RSD from 0.7% to 5.1% (n=6).Hence, baking soda added to 40% methanol water solution can be used to extract synthetic colorants from grain products with simple operation, accurate results, high efficiency and environmental protection.

Objective: The flavor formation process of stewed pork was investigated in this study. Methods: Electronic nose and gas-phase mass spectrometry （GC-MS） techniques were used to compare the key processes such as bleaching, frying, stewing and addition of sauces during the processing of stewed pork, and to analyze the changes of flavor compounds. Results: The results of electronic nose measurement were consistent with the results of gas chromatography analysis. The flavor content of raw pork and sauces was the highest, and the flavor substances decreased in the blanching, frying and stewing stages. However, the characte-ristic flavor substances were formed continuously. A total of 148 compounds were detected by GC-MS, including 39, 32, 23, 20, 38, and 65 compounds in raw pork, blanched, fryed, stewed and finished products and sauces, respectively, which mainly produced aldehydes and ketones, esters and alcohols, heterocyclic compounds, and aromatic hydrocarbons and their derivatives. The characteristic flavors of finished products were hexanal, benzaldehyde, 1-octen-3-ol, cinnamaldehyde, 2-pentylfuran, 2-acetyl pyrrole, 2,3-dimethyl-5-ethylpyrazine, etc. The content of acetoin was higher in the pre-preparation stage of stewed pork, while methoxy-phenyl-Oxime stayed high in all of the processes. Conclusion: The electronic nose technique can be used to detect the changes of flavor substances in different processing stages of stewed pork, but the specific substance changes need to be determined and analyzed by GC-MS.

Abstract Background Sodium butyrate (NaB) is produced through the fermentation of dietary fiber that is not absorbed and digested by the small intestine. Purpose Here, we aimed to investigate the effects of NaB on the proliferation, invasion, and metastasis of CRC cells and their potential underlying molecular mechanism(s). Methods The cell counting kit-8 (CCK-8) assay and EdU assay were used to detect cell proliferation ability, flow cytometry was used to investigate the induction of apoptosis and cell cycle progression, and the scratch-wound healing and transwell assays were used to evaluate cell migration and invasion, respectively. The human CRC genome information for tissues and CRC cells treated with NaB obtained from the NCBI GEO database was reannotated and used for differential RNA analysis. Functional and pathway enrichment analyses were performed for differentially expressed lncRNAs and mRNAs. A protein-protein interaction (PPI) network for the hub genes was constructed using the Cytoscape software. Targeted miRNAs were predicted based on the lnCeDB database, and a ceRNA network was constructed using the Cytoscape software. The Kaplan-Meier method was used to analyze patient prognosis using the clinical information and exon-seq data for CRC obtained from the Broad Institute’s GDAC Firehose platform. Results NaB decreased the proliferation ability of CRC cells in a dose- and time-dependent manner. The number of apoptotic CRC cells increased with the increase in NaB concentrations, and NaB induced a G1 phase block in CRC cells. Moreover, NaB suppressed the migratory and invasive capabilities of CRC cells. There were 666 differentially expressed mRNAs and 30 differentially expressed lncRNAs involved in the CRC inhibition by NaB. The PPI network and ceRNA network were constructed based on the differentially expressed mRNAs and lncRNAs. Three differentially expressed mRNAs, including HMGA2, LOXL2, and ST7, were significantly correlated with the prognosis of CRC. Conclusion NaB induces the apoptosis and inhibition of CRC cell proliferation, invasion, and metastasis by modulating complex molecular networks. RNA prediction and molecular network construction need to be the focus of further research in this direction.

In spite of the high electrical conductivity of carbon nanotube (CNT), its tendency to aggregate and expensive cost in fabricating aerogel, foams, and porous materials remains a problem. Therefore, we described a simple and feasible way to design light-weight, high electrically conductive, and cost-efficient polylactic acid (PLA)/CNT foams. The branched PLA (BPLA) resin with excellent melt elasticity and foamability was induced by nucleophilic ring-opening reaction of epoxy-based acrylic/styrene copolymer and PLA. After that, BPLA/CNT composites and foams were prepared by melt-mixing and supercritical carbon dioxide foaming technology, respectively. The thermal, electrical, and foaming properties were studied. The resultant BPLA/CNT foam possessed a low density of 0.174 g/cm3 and high crystallinity of 3.03%. An improvement of the oriented structure of CNT induced by cell growth in BPLA matrix increased the conductivity of the foam up to 3.51 × 104 Ω/m. The proposed foaming materials provided a way for designing and preparing high performance CNT products.

The effects of the cell size and distribution on the mechanical properties of polypropylene foam were simulated and analyzed by finite element modeling with ANSYS and supporting experiments. The results show that the reduced cell size and narrow size distribution have beneficial influences on both the tensile and impact strengths. Decreasing the cell size or narrowing the cell size distribution was more effective for increasing the impact strength than the tensile strength in the same case. The relationship between the mechanical properties and cell structure parameters has a good correlation with the theoretical model.

Herein, the single-track and block samples of 24CrNiMo alloy steel were prepared by selective laser melting (SLM) technology and laser melting deposition (LMD) technology. The phase composition, microstructure, texture types and micro-hardness of 24CrNiMo low alloy steel under two laser irradiation conditions were studied. The results show that the main phase compositions of 24CrNiMo alloy samples prepared by two methods are α-Fe phase and a small amount of Fe3C.Furthermore, the grain orientation of SLM single-track deposited sample is random and disordered, and there is no obvious preferred orientation.However, the preferred orientation of LMD single-track deposited sample is the (110)〈101〉 plane texture. The grain of SLM block sample has weak 〈111〉 texture parallel to the deposition direction, LMD block sample has strong texture with the 〈111〉epitaxial growth orientation.Additionally, the main microstructure of as-built SLM sample is lower bainite, and the microstructure of as-deposited LMD sample mainly consists of lathbainite. The average micro-hardness SLM sample with fine grain and lower bainite microstructure is higher than that of LMD sample.

Highly thermally conductive boron nitride (BN)@ultra-high molecular weight polyethylene (UHMWPE) composites with the segregated structure were fabricated by powder mixing and hot pressing. Scanning electron microscopy and polarizing optical microscopy were used to analyze the dispersion of BN particles in the UHMWPE matrix. The morphology observation shows that BN particles are selectively located at the interfaces of UHMWPE particles and form continuous thermally conductive networks after the compression molding process. As a result, the thermal conductivity of the BN@UHMWPE composite increases to 3.37 W m−1 K−1 with 38.3 vol% BN, which is seven times larger than that of the pure UHMWPE. Furthermore, the incorporation of BN also influences the crystallinity and thermal properties of UHMWPE.

Among the manufacturing methods of high performance gradient functional materials, laser additive manufacturing technology can achieve the materials with gradient microstructure and property through precisely controlling the powder feeding and corresponding process adjustment, providing a new way to prepare high performance gradient functional materials more conveniently and efficiently. The basic principles and classification of laser additive manufacturing technology for high performance gradient functional materials were introduced in this paper, and the research progress in manufacturing high performance gradient functional materials by laser additive manufacturing technology at home and abroad was summarized. Furthermore, the shortcomings of this research field in material selection, process optimization and process monitoring were proposed, and its future research directions, such as the establishment of standard systems, in-depth theoretical research and the development of new manufacturing systems, were prospected, which provide guidance for the research of laser additive manufacturing technology for high performance gradient functional materials.

BACKGROUND The abundances and variation characteristics of silver, boron and tin reflect the regional metallogenic conditions and indicate the existence of deposits or mineralization. Silver, boron and tin in carbonate minerals are elements that must be determined in exploration geochemistry and multi-objective geochemistry. The analytical method was one of the essential methods in the matching analysis scheme of geochemical elements. Because carbonate minerals are different from common rocks, soils and water-based sediments, these minerals are mainly limestone, dolomite and other rock samples with relatively high calcium and magnesium elements, and the technical difficulty in determining silver, boron and tin in these samples is that the high content of calcium and magnesium matrix will seriously disturb the elements with low contents to be measured, and the sample is easily contaminated due to carbon dioxide during the spectrum recording process. OBJECTIVES To solve the problems of rapid and accurate determination of silver, boron and tin in carbonate minerals. METHODS In view of the particularity of carbonate minerals, an analytical method for the simultaneous determination of silver, boron and tin in carbonate minerals by alternating current-arc optoelectronic direct reading-optical spectrometry (AC-Arc-OES) was established. RESULTS By using 10% hydrochloric acid to digest the sample, the interference of matrix elements, calcium and magnesium, was eliminated. Germanium was used as the internal standard element for quantitative analysis, which eliminated the influence of external factors, such as the change of arc excitation conditions and matrix composition of the sample. The silver element and the long wave germanium element were used to form the analysis line pair, and the boron and tin element and the short wave germanium element were used to form the analysis line pair with good sensitivity. Twelve national geochemical reference materials, such as natural carbonate rock and synthetic limestone, were selected as the standard series. The matrix components were similar to those of the samples. The method of off-line subtraction was used to correct the background. The detection limits of the method for silver, boron and tin were 0.008μg/g, 0.49μg/g and 0.18μg/g, respectively. The precision of the method was larger than 10% for silver, and that of other elements was better than 10%. The accuracy of the method was verified by the national level geochemical reference materials, and the logarithm difference between the average value and the certified value of the reference materials was less than or equal to ±0.05. CONCLUSIONS This method was used to solve the problem of rapid determination of silver, boron and tin in carbonate minerals. It is simple and fast, and suitable for the determination of a large numbers of samples. All of the technical indices of the method meet the requirements of multi-objective regional geochemical survey specifications.

In order to improve the corrosion resistance and wear resistance of magnesium alloy efficiently and environmentally, the corrosion resistant and wear resistant coating were prepared on AZ91D magnesium alloy by direct electroless nickel plating without fluorine, chromium, cyanogen and zinc. The surface morphology, composition, phase and corrosion resistance properties were characterized and compared by SEM,EDS,XRD and electrochemical workstation respectively. The results show that the coatings are smooth and compact, consisting of fine and uniform cellular structure being mainly composed of 85.25%(mass fraction) amorphous Ni and P in the ratio of main salt to reductant is 1:1.4,complexing agent concentration is 16 g·L-1, pH=7 and the temperature is (85±0.5) ℃.The hardness is increased from 72HV of substrate to 285HV. Corrosion potential is enhanced from -1.524 V(substrate) to -0.513 V, meanwhile the corrosion current density is decreased by about 3 orders of magnitude. The cohesion between the substrate and the deposition layer is good without peeling and falling off, and the thickness of the deposition layer is approximately 38 μm.

The surface treatment was carried out on the surface of materials of A473M martensitic stainless steel axle sleeve by rolling technology, aiming to investigate the effect on its mechanical properties. The surface morphology and roughness, residual stress, microhardness, tensile and fatigue property were systematically studied using the SEM, white light interferometer, X-ray diffractometer, microhardness tester, EBSD, tensile tester and fatigue tester. The results show that the surface roughness of rolling specimen reduces significantly, which is about 1/5 of that of turning surface. The residual compression stress is induced near surface by rolling processing, the maximum value can reach up to 946 MPa and the residual compression stress decreases along with the depth. The thickness of the residual compression stress layer is about 200 μm. In addition, the rolling surface microhardness can be improved by 30% compared with that of turning surface and the hardened layer can be about 200 μm. As for mechanical properties, the tensile strength, yield strength and elongation of rolling specimens increase about 40%, 22% and 8% respectively compared with that of turning specimens. The fatigue life increases from 5.4×104 cycles to 1×107 cycles after rolling processing. The mechanical properties of the rolled material significantly improve, and the fatigue life significantly increases.

According to the World Meteorological Organization, “record” greenhouse gas concentrations and heat accumulation have pushed the planet into uncharted territory, driving global warming. We need to figure out how to mitigate global warming by maximizing the overall benefits of forests based on the optimal deforestation period. This provides a basis for decision-making for forest managers. At the micro level, we only consider the carbon sequestration capacity of individual trees. AHP was used to determine the more important influencing factors. The S-curve model was fitted by single-factor and multi-factor analysis to obtain the carbon sequestration saturation point. It should be cut down at the saturation point of carbon sequestration. At the macro level, we consider the carbon sequestration capacity of forests. Therefore, from the economics perspective, we construct a carbon sequestration benefit model based on the optimal rotation period and deduce the optimal and maximum carbon sequestration benefits.

BACKGROUND Copper nickel and zinc concentrates all belong to metal sulfide minerals and are import commodities. The rapid and accurate analysis of dispersed elements in these samples is beneficial to the comprehensive utilization of mineral. However, the content of rare elements in such minerals is extremely low, and the properties of each element are different. In particular, Ge and Se cannot be precisely determined due to volatilization loss in wet digestion, and it is difficult to simultaneously measure various elements. OBJECTIVES To simultaneously determine the various elements in the sample. METHODS Copper, zinc and nickel concentrates were used as representative sulfide minerals. The sample was pre-sealed by microwave digestion, and the content of rare elements was determined by inductively coupled plasma-mass spectrometry (ICP-MS). Simultaneous determination of various elements was realized. The experimental conditions of total solid solution, internal standard, mass spectrum interference elimination and pretreatment acid selection were compared. RESULTS During determination of Ga, Ge, Se, Cd, In, Te, La and Tl by microwave digestion in ICP-MS analysis, total amount of solid solution, internal standard, and mass spectrum interference elimination conditions was consistent in three types of metal sulfide ores. Unfortunately, the acid types were not the same. HNO3-HCl-HF-H2O2 system was more suitable for measuring Ga, Ge, Se, Cd, In, Te, La and Tl in nickel and zinc concentrates, and Ga, Ge, Se, Cd, In, La and Tl in copper concentrate. The recoveries of these elements ranged from 85.5% to 116.6%. The HCl-HNO3 (3:1) system was more suitable for detecting Te in copper concentrate. CONCLUSIONS The method is simple, and the simultaneous determination of multiple elements is realized. Other factors of the method are the same, the acid digestion system is the key to selection.

To explore the effects of self-directed learning readiness and learning attitude on problem-solving ability among Chinese undergraduate nursing students.

The objective of this research is to investigate the expression and function of SKA3 in lung adenocarcinoma.

The surface treatment was carried out on the surface of materials of A473M martensitic stainless steel axle sleeve by rolling technology, aiming to investigate the effect on its mechanical properties. The surface morphology and roughness, residual stress, microhardness, tensile and fatigue property were systematically studied using the SEM, white light interferometer, X-ray diffractometer, microhardness tester, EBSD, tensile tester and fatigue tester. The results show that the surface roughness of rolling specimen reduces significantly, which is about 1/5 of that of turning surface. The residual compression stress is induced near surface by rolling processing, the maximum value can reach up to 946 MPa and the residual compression stress decreases along with the depth. The thickness of the residual compression stress layer is about 200 μm. In addition, the rolling surface microhardness can be improved by 30% compared with that of turning surface and the hardened layer can be about 200 μm. As for mechanical properties, the tensile strength, yield strength and elongation of rolling specimens increase about 40%, 22% and 8% respectively compared with that of turning specimens. The fatigue life increases from 5.4×104 cycles to 1×107 cycles after rolling processing. The mechanical properties of the rolled material significantly improve, and the fatigue life significantly increases.

Assembly On-orbit is a modular design idea to solve the problem of the super-large-aperture space telescope realization. The sub-mirror modules of the spliced primary mirror require precise installation and positioning to meet the optical and structural requirements. A docking locking device for sub-mirror modules of Assembled telescope is developed in this paper. The structure, working principle and component selection of the device are described, and the key parameters of the positioning and locking mechanism are designed. The experimental results show that the repeatability XYZ of the docking locking device is better than ±0.02 mm, the locking force is not less than 2000 N. The device is accurately positioned and locked reliably, meeting the installation requirements of the sub-mirror module, and providing a precise benchmark for the later active optical adjustment of the assembled telescope sub-mirror module.