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Objective Sb deposits are characterized by simple mineral assemblage. The ore-forming ages, sources of ore-forming materials, and genesis of Sb deposits are controversial owing to the absence of suitable minerals for analysis. Sb resources in the South China Sb metallogenic region account for over 83% of the national total, with the Dian–Qian–Gui Sb belt in the southwest being an significant component of this region. Methods Taking the Longlin–Xilin Sb–Au mining district of western Guixi in the central part of the Dian–Qian–Gui Sb belt as an example, this paper systematically summarizes the ore-bearing strata, lithology of ore-bearing wall rocks, ore-bearing structures, and the coexistence relationship of Au and Sb deposits in 86 ore deposits (points) in the area. Combined with the geological characteristics of three typical deposits (Maxiong, Longtan, and Mahao) and the spatiotemporal distribution of Jurassic felsic intrusions, the inherent connection between Sb mineralization and clastic rocks and felsic intrusions was explored. Results (1) Statistics and field works show that the most favorable ore-bearing stratum in the Longlin–Xilin mining district is the Lower Devonian Yujian Formation (D1y) , followed by the Lower Triassic Luolou Formation (T1Ll) and the Middle Triassic Banna Formation (T2b). The lithologies most conducive to mineralization are carbonaceous shale, pyrite-rich sandstone, and siltstone. The Sb content in these strata or lithologies is tens or even hundreds of times higher than the crustal abundance, which has the potential for Sb mineralization. (2) Within the NWW–SEE trending Nongsang–Shijiazhai fault zone in the Longlin area, the middle and late Jurassic felsic intrusions, which have consistent spatiotemporal occurrences with Sb and Au deposits, can directly contribute to antimony mineralization (as sources of Sb and S) and indirectly influence it (as a heat source), both favoring the formation of antimony deposits. (3) Statistical results show that Sb, Au, and Sb–Au deposits account for 48%, 46%, and 6% in the Longlin–Xilin district, respectively. This suggests that the ore-forming fluids for Sb and Au in the study area may originate from different sources. We also can not rule out the possibility that Sb and Au deposits derive from the same fluid. In the latter case, the precipitation of stibnite consumes H2S in the ore-forming fluid, destabilizing the Au complex in the solution and resulting in localized Au precipitation. This competition between Sb and Au in the fluid for H2S leads to a negative correlation in the grades of Sb and Au in coexisting deposits. (4) The study area experienced NS-striking compression in the Indosinian period, followed by the NW–SE shortening in the middle–late Jurassic. The intersection of NWW–SEE and NE–SW faults is the favorable ore-bearing space. The NWW–SEE faults displayed strike-slip movement in response to the NW–SE shortening, whereas the NE–SW faults exhibited transpression. Consequently, the NE–SW faults are less conducive to Sb mineralization compared to the NWW–SEE faults. The distribution direction of the NWW–SEE Douhuang–Xilin fault aligns with the axial direction of the main folds in the area, with most fault planes trending northward, displaying horizontal scratches, silicification, and extensional characteristics. The intersection of the Dohuang–Xilin fault and the NE–SW fracture exhibits significant Sb anomalies. Conclusion Based on the above studies, the promising areas we propose for Sb prospecting in Longlin–Xilin mining district are (1) Black shale and pyrite-rich siltstones of the Yujiang Formation in the core of the Xinzhou anticline as the key strata; (2) The periphery of the concealed intrusions within the NWW–SEE Nongsang–Shijaizhai fault (Longlin County) and the intersection area of the NWW–SEE Douhuang–Xilin fault and the NE–SW fault as the favorable areas. [ Significance ] The findings provide new insights into the genesis and metallogenic regularities of Sb–Au deposits in the study area, enriching the theoretical understanding of Au mineralization processes.

Objective To explore the causal relationship between depression and the risk of cervical cancer by Mendelian randomization(MR). Methods Based on Genome Wide Association Study(GWAS) data, single nucleotide polymorphism(SNP) associated with depression were selected as genetic instrumental variables. Three Mendelian randomization methods, inverse variance weighted analysis(IVW), weighted median methods and MR-Egger were used to investigate the causal association between DP and the risk of cervical cancer. Radial MR was used to identify outliers. The analysis results were shown by odds ratio(OR)and 95% confidence interval(CI), and the effect was statistically significant with P＜0. 05. Results Totally 57 SNPs related to depression were included. The result of IVW show that depression was a risk factor for the risk of cervical cancer(OR=1. 002, 95%CI: 1. 0002～1. 003, P=0. 03). Weighted median method and MR-Egger provided the similar result. Sensitivity analysis found that no single SNP was strongly or reversely driving the overall effect for causal estimates. Conclusion Depression was a risk factor of cervical cancer. Strengthening the screening and prevention of cervical cancer in DP patients was of great significance to reduce the incidence of cervical cancer in this population. (目的 通过孟德尔随机化(MR)方法, 探究抑郁与宫颈癌发病风险的因果关联。方法 以全基因组关联分析研究(GWAS)数据为基础, 筛选出与抑郁的关联单核苷酸多态性(SNP)作为基因工具变量, 利用逆方差加权分析方法(IVW)、加权中值方法和 MR-Egger 方法三种孟德尔随机化方法探究抑郁与宫颈癌发病风险的因果关联。采用Radial MR用来识别异常值。分析结果以比值比(OR)和 95%可信区间(CI)显示, P＜0. 05 为效应具有统计学意义。结果 共筛选到57个与抑郁相关的SNP。 IVW 结果显示, 抑郁是宫颈癌发病风险的危险因素［OR=1. 002, 95%CI (1. 0002～1. 003), P=0. 03］; 加权中值法和 MR-Egger 效应估计值具有相似的统计结果。敏感性分析发现没有对因果估计结果产生较大的 SNP。结论 抑郁是宫颈癌发病风险的危险因素, 加强抑郁患者宫颈癌的筛查、预防以及健康宣教, 对于降低该人群的宫颈癌发病率具有重要意义。)

Combined heat and power (CHP) system has the outstanding advantages of environmental protection,economy and flexible operation mode,and has a better development prospect. Based on the different characteristics of electricity and heat in transmission and storage,a two-stage optimal scheduling method for CHP system considering thermal inertia is proposed. In the first stage,considering the structure and operation characteristics of the heating network,the optimal scheduling model of the CHP system based on model predictive control is established,and the strategy of intra-day controllable equipment output and grid interactive power is optimized. In the second stage,the goal is minimize the output adjustment of each unit in CHP system,and the real-time prediction error of renewable energy and load is taken into account to dynamically adjust the economic scheduling strategy in the first stage. The example shows that the two-stage optimal scheduling model can improve the economy of system operation and make up for the imbalance of supply and demand. Combined with the thermal inertia of the system,the building can store or release heat according to load demand and time-of-use electricity price,which can reduce the impact of renewable energy and load uncertainty on scheduling,smooth power fluctuations,and promote heat and power complementation.

The different heat transfer conditions in each region of the vacuum arc remelting superalloy ingot lead to significant difference in the morphology and size distribution of carbide in the ingot. Based on industrial vacuum arc remelting GH4742 alloy as a raw material, using metallographic and scanning electron microscopic analysis quantitative analysis method to study the ingot different position distribution of the carbide precipitation behavior and microstructure, supplemented by MeltFlow-VAR simulation software, the solidification process of remelting different cooling rate and local solidification time on the influence of carbide were analyzed. The results show that Nb and Ti elements are enriched in the carbide precipitates of GH4742 alloy, and the segregation degree of Nb element is the largest. The area of the precipitated phase is decreased from the center to the edge, and the morphology is changed from skeleton-like and cursive to interconnected fine strips. As the cooling rate increases, the dendrites become more slender and compact, and the dendrite spacing decreases. The area of precipitated phase is linearly related to the secondary dendrite spacing. Increasing the cooling rate can reduce the dendrite spacing, thus the area of precipitated phase is reduced effectively.

Long-term bed rest may result in skin surface pressure, and primary prevention is to redistribute pressure by turning the patient, therefore reducing the risk of pressure ulcer development. Turning apparatus is designed to help to turn the long-term bedridden patient. This paper introduced several turning apparatuses such as pillow, mattress, a comparison of different apparatuses was also made to provide better choice of turning apparatus for long-term bedridden patients. (患者长期卧床易导致局部皮肤受压, 翻身能够减轻长期卧床患者局部受压的情况, 能有效降低长期卧床患者患压疮的风险。翻身用具对协助卧床患者翻身有积极意义, 本文归纳介绍了近年来临床翻身用具如翻身枕、翻身床垫等的研究进展, 并对各种翻身用具进行比较, 以期为长期卧床患者对翻身用具的选择提供参考。)

Objective To establish the nomogram and predict the risk factors of wound complication in patients with emergent abdominal surgery via a midline vertical incision. Methods The clinical data of 247 patients treated in Department of Surgery Ruijin Hospital including 68 cases with wound complication and 139 cases without wound complication were collected and analyzed. Risk predictors were selected from the items of clinical strategies by the least absolute shrinkage and selection operator (LASSO) regression model and multivariable logistic regression analysis was performed with incorporated items. C-index and calibration plot were used to evaluate the discrimination and calibration of prediction model. Results Six items including age ≥60 years, smoking and history of abdominal surgery, preoperative lower albumin in serum and increase in C-reactive protein level, and both continuous and interrupted suture of abdominal incision were included in the prediction model. The prediction model showed better discrimination and calibration with a C-index of 0.747 (95%Cl: 0.678-0.816). Conclusions The established nomogram can be used to predict the risk of wound complication in patients with emergent abdominal surgery via abdominal midline vertical incision.

Fe-Bi24O31Cl10 photocatalytic materials were prepared by modified solution combustion method using bismuth nitrate, citric acid, ammonium chloride and ferric nitrate as raw materials. The influence of Fe3+ doping on its photocatalytic performance was evaluated by degrading rhodamine B in visible light.XRD,XPS,UV-vis, SEM,HTEM and FT-IR were used to study the effects of different Fe3+ doping amount on the phase, elemental valence, optical absorption performance, microscopic morphology and particle distribution, crystal surface spacing and chemical structure composition of Bi24O31Cl10.The results show that doped Fe3+ does not change the phase and morphology of Bi24O31Cl10, but its sheet size is obviously smaller, its thickness is thinner, its optical absorption property is enhanced, and the photoelectron hole recombination ratio is decreased. Compared with pure Bi24O31Cl10, Fe3+ doping can significantly improve the photocatalytic activity of Bi24O31Cl10.The photocatalytic activity of Bi24O31Cl10 is the highest when the doping amount of Fe3+ is 0.5% (mole fraction), and the decolorization rate of RhB is 75% when exposed to visible light for 50 min, which is 44% higher than that of pure Bi24O31Cl10.

Fe-Bi24O31Cl10 photocatalytic materials were prepared by modified solution combustion method using bismuth nitrate, citric acid, ammonium chloride and ferric nitrate as raw materials. The influence of Fe3+ doping on its photocatalytic performance was evaluated by degrading rhodamine B in visible light.XRD,XPS,UV-vis, SEM,HTEM and FT-IR were used to study the effects of different Fe3+ doping amount on the phase, elemental valence, optical absorption performance, microscopic morphology and particle distribution, crystal surface spacing and chemical structure composition of Bi24O31Cl10.The results show that doped Fe3+ does not change the phase and morphology of Bi24O31Cl10, but its sheet size is obviously smaller, its thickness is thinner, its optical absorption property is enhanced, and the photoelectron hole recombination ratio is decreased. Compared with pure Bi24O31Cl10, Fe3+ doping can significantly improve the photocatalytic activity of Bi24O31Cl10.The photocatalytic activity of Bi24O31Cl10 is the highest when the doping amount of Fe3+ is 0.5% (mole fraction), and the decolorization rate of RhB is 75% when exposed to visible light for 50 min, which is 44% higher than that of pure Bi24O31Cl10.

[Objectives] Cogging torque has an important influence on the blade vibration of a Rim-Electric Driven Propeller (REDP). In order to investigate a method for reducing the cogging torque of REDP, this paper analyzes the combination of slot number, pole number, tooth shape and pole arc coefficient on the influence of cogging torque.[Methods]First, according to the Ka4-50 propeller model parameters and the design standards of the Permanent Magnet Brushless DC Motor, a 36-slot and 26-pole driven motor is designed. The magnetic circuit calculation software Maxwell Rmxprt is then used to analyze the influence of different slot number and pole number combinations, tooth shape and pole arc coefficient on the motor.[Results] The results show that for a frictional slot and concentrated windings motor, the amplitude of the cogging torque is inversely proportional to the lowest common multiple. Among opening slots, closed slots and half-closed slots, half-closed slots have the greatest torque, opening slots have less and closed slots have the least. The influence of pole arc coefficient on cogging torque shows a fluctuation rule. In the design, it is necessary to find the extreme pole arc coefficient corresponding to the minimum value of the cogging torque through specific analysis.[Conclusions] This paper provides references for the overall design of REDP and a theoretical basis for further exploring the influence of the motor on the vibration and noise of REDP.