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The open field subsequent filling method in segmented drilling stage is an efficient mining method for inclined medium thick ore bodies.However, blasting, filling and stope stability show complex relationships, causing surface subsidence, roof and floor collapse, and high mining loss rate.This study adopts engineering analogy and industrial experiments to optimize the process of the sublevel drilling and stage open-stoping with backfill of inclined medium thick ore bodies in the aspects of mining sequence, cutting method, and bottom structure layout, and propose a layout method without leaving pillars in the stope.This method directly connects the side walls of the filling body to the chamber after one-step of filling, and improves the strength of the filling body and the recovery rate of the ore block through extrusion blasting.As the key to this method lies in the implementation time, numerical simulation using ANSYS/LS-DYNA shows that medium-depth hole extrusion blasting is used to form cutting grooves, it should be carried out between 7~9 d after filling and curing of the filling body in the stope.Engineering practice has proved the feasibility of this method, which provides technical support for mining production.

IntroductionThe spiral tube heat storage tank is a highly efficient device designed for storing and releasing heat, utilizing a spiral tube structure. Its key advantages include efficiency, reliability, and flexibility, making it suitable for a wide range of conditions, from high temperatures and pressures to low temperatures and high vacuums.MethodsThis study aims to analyze phase change heat storage in spiral tube heat storage tanks using numerical simulation.ResultsIt explores the impact of varying water supply temperatures on heat transfer efficiency and the melting behavior of phase change materials within the tanks. Proposed enhancements, informed by numerical simulation results, seek to improve heat transfer efficiency. Simulation findings indicate that charging efficiency rises with increased temperature differentials, akin to sleeve-type heat exchangers.DiscussionCalculations suggest faster melting of phase change materials at the central position of the tank’s spiral tube, with slower melting near the vessel wall. Consequently, reducing the number of spiral tubes in the middle is suggested for future structural optimization.

C15H8F4N2O3, monoclinic, P21/n (no. 14), a = 11.2759(7) Å, b = 9.0182(5) Å, c = 14.2235(8) Å, β = 93.834(2)°, V = 1443.13(15) Å3, Z = 4, Rgt (F) = 0.0391, wRref (F 2) = 0.1067, T = 273.15 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.

China’s food system is transforming from providing adequate and safe food to supplying nutritious and healthy food as the country develops into a new stage of comprehensive modernization. To be green and low-carbon has become the global consensus regarding food system transformation, and China plans to transform its food system to be inclusive and sharing. Currently, China’s food system faces multiple challenges such as the coexistence of overnutrition and nutritional deficiency, contradiction between supply assurance and carbon reduction, lack of tolerance for small-scale farmers and vulnerable groups of consumers, and weak resilience in production stability and supply controllability. Against the background of a declining population and an increasing urbanization rate, the structure of China’s food system needs to be further optimized and develops toward “nutrition and health, green and low carbon, inclusiveness and sharing, and safety and resilience”. Future efforts should focus on (1) adjusting the production system to enrich food supply, (2) strengthening scientific and technological innovation by prioritizing the development of win-win technologies, (3) improving relevant policies to increase investment in the transformation, (4) optimizing existing systems and mechanisms to build an efficient and inclusive food chain, and (5) promoting low-carbon consumption concepts and behaviors. Furthermore, we propose the following suggestions: (1) initiating nutrition-related legislation at the national level, (2) establishing a national reserve for food system transformation technologies, (3) launching a national science and technology project for food system transformation and upgrading, and (4) launching a national nutrition and health campaign.

Accurate identification and effective control of food security risks are crucial for national security. This study constructs a food security risk system that comprises nine major types of risk sources from the perspective of the entire industrial chain. Our research identifies seven main risks that China’s food security faces at the new stage: relatively lagging breeding technologies, prominent contradiction between resource supply and demand, frequent disasters, significant decline in farmers’ willingness to grow grains, increased uncontrollability of market trade, inadequacy in policy compliance and stability, and frequent impacts of unexpected events. Based on this, a strategic concept is proposed, that is, a food security risk management and control system that combines early identification, normal monitoring, and emergency warning and is capable of entire industrial chain risk identification, whole-process management, and multi-level linkage. Furthermore, the following strategies for controlling food security risks are proposed: (1) promoting food security legislation, (2) launching a key scientific and technological project for constructing a national food security risk control system, (3) improving infrastructure and defense systems, and (4) optimizing market-oriented means and tools for risk management. The research results are expected to provide decision-making references for promoting the modernization of China’s food security governance system and capacities.

Introduction: Cavability issues often arise in hard rock mines employing the block caving mining method. Hydraulic fracturing stands out as a promising pre-conditioning technology for hard rock masses, with its pre-conditioning effects dependent on variable parameters.Methods: The impact of cluster number, injection rate, and liquid volume on fracture propagation was investigated through on-site hydraulic fracturing practices. Fracturability was initially verified via true triaxial fracturing tests, and preconditioning parameters were subsequently optimized using numerical simulations. The optimized on-site construction was monitored using electromagnetic methods.Results: The study revealed a negative correlation between fracture radius and the number of clusters, gradually decreasing with an increase in cluster number. However, the fracture weakening area increased with the rise in the number of clusters. The fracture weakening area also increased with the injection rate. Additionally, the fracture radius initially increased and then decreased. Both fracture weakening area and radius increased with an increase in liquid volume. The optimized parameters were identified as four clusters, an injection rate of 4 m3/min, and a liquid volume of 500 m3.Discussion: Building upon these findings, on-site experiments were conducted and monitored using electromagnetic methods. The monitored results demonstrated that the optimized parameters effectively achieved hydraulic fracturing expansion, accomplishing the goal of weakening hard rock.

In view of the problems of low yield of enzymatic conversion of ginsenoside Rb1 in traditional buffer solution, low solubility of intermediates and slow enzymatic conversion rate, ginsenoside Rb1 was converted by deep eutectic solvent auxiliary enzymatic method. The effects of DES types and mass concentration, pH value, temperature, enzyme-substrate mass ratio and reaction time on CK yield were investigated, and the optimal conditions for the conversion reaction were obtained in DES buffer with pH=5.3, the mass ratio of snail enzyme to substrate was 1∶1, and the yield of CK could reach 87.92% at 50 ℃ and the reaction for 36 h. The method of dissolving ginsenosides in DES solvent for enzymatic conversion was adopted, which can better increase the solubility of ginsenosides, enhance the secondary structure of enzymes, and improve the yield of CK, the preparation process is environmentally friendly, safe and suitable for industrial production.

Promoting the competitiveness of China’s agricultural industry is crucial for building China into a great modern country. The aggravation of agricultural external risks and the basic national conditions—smallholder farmers, resource shortage, and tight balance of agricultural products supply and demand—propose new requirements and challenges to the competitiveness of China’s agricultural industry. It becomes urgent to redefine the competitiveness of agricultural industry and propose a corresponding strategic framework for the new development stage. In this study, we propose a new concept of agricultural industry competitiveness labeled as safe and diversified, green and efficient, core control, and independent competition. Moreover, we establish a competitiveness evaluation index system for the agricultural industry considering three core components: security assurance, industrial control, and market competitiveness; we evaluate the competitiveness of China’s agricultural industry using this system to explore the weaknesses of the industry. Furthermore, we propose competitiveness upgrade paths and countermeasures for China’s agricultural industry at the new stage. Specifically, China should ensure a stable supply of important agricultural products, expand the value-added space of its agricultural industry, promote the modernization of agricultural operation and services, encourage international cooperation, and give priority to the development of agricultural science and technologies.

The 2NaBH4+MgH2 and 2NaBH4+MgH2+0.1MFx (M＝Ni, Ti, Zr;x＝2, 3, 4) hydrogen storage composites were prepared by ball milling. The morphology, element distribution, and crystal structure of the composites were detected by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD), respectively. In addition, the hydrogen release thermodynamic properties of the materials were tested by differential scanning calorimetry (DSC) and temperature-programmed desorption (TPD). The results show that the peak temperature of the first hydrogen release process for 2NaBH4+MgH2 is decreased by 8.9, 35.7 ℃ and 54.5 ℃ by the addition of NiF2, TiF3 and ZrF4, respectively. In addition, the NaMgF3 phase that appeared during the hydrogen release process changes the reaction path of the first hydrogen release process, and catalyzes the second hydrogen release process of 2NaBH4+MgH2, which reduces the peak temperature of the second dehydrogenation process by 18.0 ℃, 31.1 ℃ and 34.1 ℃, respectively. The quantity ratio of hydrogen release for 2NaBH4+MgH2 reaches 91.7%, 91.9% and 98.7% by the addition of NiF2, TiF3 and ZrF4, respectively. In these three catalysts, ZrF4 shows the best catalytic effect on the entire hydrogen release process of 2NaBH4+MgH2. Therefore, 2NaBH4+MgH2+0.1ZrF4can be used as a potential application system of fuel cell hydrogen supply system.

Aesthetic medicine includes aesthetic surgery, cosmetic dermatology, aesthetic dentistry and aesthetic Chinese medicine. The goal of aesthetic medicine is to maintain, modify and remodel the beauty of appearance through medical methods. The shaping of beauty mainly relies on aesthetic surgery, which is the principal part of aesthetic medicine. With the increasing demand for beauty, the medical aesthetic industry has flourished in recent decades, and the complications of aesthetic surgery also have been rising. This article summarizes the complications related to aesthetic medicine in order to provide a warning for clinical diagnosis and treatment.

Localized scleroderma is a rare auto-immune disorder characterized by inflammation and fibrosis of the skin and subcutaneous fat in the affected area, leaving aesthetic impairment to the patients.Such patients often seek plastic surgery for the treatment. This article summarizes the pathophysiology and preoperative evaluation of localized scleroderma, discusses the progress and clinical dilemma of its surgical treatment, and shares the opinions on the diagnosis and treatment of a single center in Peking Union Medical College Hospital.

Diabetes mellitus is a n arising public health concern, and diabetic foot is one of the most common complications of diabetes. Current management for diabetic foot cannot reach optimal remission. In this study, we aim to explore the mechanism underlying the pathogenesis of diabetic foot and provide novel strategies for the treatment of diabetic foot. A total of 10 normal skin tissues and 20 diabetic foot ulcer specimens are collected. Cell proliferation is determined by CCK-8 assay. Cell cycle is determined by flow cytometry, and cell senescence is evaluated by β-galactosidase staining. Co-immunoprecipitation assay is used to explore the interaction between USP7 and p53. Advanced glycation end products (AGEs) are used to establish diabetic cell model, and streptozotocin (STZ) is used to establish diabetic rat model. Our results showed that USP7 expression is increased in diabetic foot ulcer and in human umbilical vein endothelial cells (HUVECs) after treatment with AGEs. Inhibition of USP7 can reduce cell cycle arrest and cell senescence in HUVECs. Moreover, USP7 can interact with p53 and promote its expression through mediating its deubiquitination. Knockdown of p53 can reverse USP7-mediated cell cycle arrest and cell senescence in HUVECs. In diabetic rats, HBX 41108, the specific inhibitor of USP7, can significantly accelerate wound healing. Our study reveals that the inhibition of USP7 can suppress AGEs-induced cell cycle arrest and cell senescence of HUVECs through promoting p53 ubiquitination. USP7 is a potential target for the treatment of diabetic foot ulcers.

The effects of γ-ray irradiation on the thermal stability and creep resistance of ultra-high molecular weight polyethylene (UHMWPE) were studied. First, UHMWPE powder was hot pressed into 1 mm thick sheets using a vulcanization molding machine. The chemical structure, thermal stability, microstructure, tensile properties, and creep properties of the irradiated plate samples were studied. The results demonstrated that, after γ-ray irradiation, the melting points, crystallinity, and thermal stability increased; the gel content increased to 89%; and the motility of molecular chains decreased. Compared with the creep resistance of the unirradiated sample, that of the irradiated sample increased by approximately 40%. In this study, the thermal stability and creep resistance of UHMWPE were significantly improved via the radiation cross-linking process, which provided a method for the preparation of UHMWPE materials with high creep resistance and high thermal stability.

In order to improve the optimization effect of the fruit fly optimization algorithm（FOA） on support vector machine（SVM） parameters, the evolution strategy of FOA was improved, and the duoble group coevolution fruit fly optimization algorithm（DGCFOA） was proposed in this paper. The DGCFOA was used to optimize the parameters of SVM and then used to gearbox fault diagnosis. Diagnosis results show that DGCFOA algorithm can obtained better SVM parameters when compared with FOA, it significantly improved fault diagnosis accuracy of gearbox. In addition, the diagnosis results also show that DGCFOA has higher diagnostic accuracy and more obvious advantages when compared with some other methods.

This paper analyzed the clinical data of 5 patients with skin rash caused by pegylated interferon α-2a combined with ribavirin therapy of chronic viral hepatitis C. According to the clinical symptoms, patients were given internal administration of Chinese herbal medicine decoction combined with external wash of Chinese herbal medicine decoction. Comprehensive interventions including skin care, infection prevention, nutrition support and psychological nursing were carried out during the treatment. (本文回顾聚乙二醇干扰素α-2a联合利巴韦林抗病毒治疗慢性丙型肝炎过程中出现皮疹(斑丘疹型)的5例患者的临床资料, 总结相关护理措施。结合患者中医证候表现, 辨证给予中药汤剂内服联合中药汤剂外洗患处, 同时配合实施皮肤护理、预防感染、营养支持、心理护理等措施。)

The effects of γ-ray irradiation on the lipophilic and hydrophobic properties of two types of polypropylene (PP) foam materials were systematically studied. Isotactic polypropylene (iPP) and high-melt-strength polypropylene (HMSPP) sheets were prepared by hot pressing with a thickness of 1 mm, and then PP foams were prepared by supercritical CO2 batch foaming. Finally, the foamed samples were irradiated with γ-rays. The results showed that the melting points and crystallization temperatures of the two foams decreased after irradiation. The scanning electron microscope images showed that the cell walls of both PP foams appeared cracks and the roughness of the foam’s cross-section increased significantly. The water contact angle of iPP foam largely increased by 26.4%, and the contact angle of HMSPP foam increased from 135.2° to 141.8°, which almost reached the super-hydrophobic level. The enhanced roughness increased the hydrophilic defects and the droplet adhesion resistance. Moreover, the appearance of the cracks in the cell walls increased the connectivity between cells, which largely increased the foam oil absorption permeability and the oil absorption quantity. This study provides a method for preparing lipophilic and hydrophobic foam.

Objective To compare the perioperative outcomes and long-term efficacy of laparoscopic liver resection (LLR) and open liver resection (OLR) for hepatocellular carcinoma originating in the paracaval portion, and explore the safety and feasibility of LLR in treatment of paracaval-originating tumors. Methods Forty-two paracaval-originating tumor patients admitted in our hospital from May 2013 to May 2020 were enrolled in this study. The median follow-up time of the patients was 27.5 months in the LLR group and 26.0 months in the OLR group. Perioperative outcomes and long-term effect were analyzed retrospectively. Results There were 21 patients undergoing LLR and the other 21 OLR, and no perioperative death occurred. One case of the LLR group was converted to OLR during operation. There were no significant differences in operation time, blood loss, intraoperative transfusion rate, resection margin of malignant tumour or postoperative complications. The LLR group obtained earlier postoperative feeding (P=0.042), shorter length of hospital stay (P=0.008), and lower postoperative total bilirubin at 1, 3 and 7 d after surgery (P=0.004, 0.010, 0.018) when compared with the OLR group. What's more, no obviously differences were seen in 1- and 3-year overall survival rates (100.0% vs 87.5%, P=0.292; 87.5% vs 68.8%, P=0.326) or in 1- and 3-year disease-free survival rates (62.5% vs 50.0%, P=0.488; 50.0% vs 37.5%, P=0.455) between the 2 groups. Conclusion LLR is safe and feasible for paracaval-originating tumours in selected patients, with the advantages of earlier postoperative feeding and shorter hospital stay.

Objective To investigate whether miR-186-5p can regulate the proliferation and apoptosis of islet β-cells induced by high fat and high glucose through cell division cycle associated 3 protein (CDCA3). Methods Mouse pancreatic β-cell line NIT-1 was treated with high lipid and glucose to induce injury. CCK-8 assay and flow cytometry were employed to measure cell proliferation and apoptosis. The expression of Ki-67, PCNA, Bcl-2 and Bax at protein level was analyzed by Western blotting, while that of miR-186-5p and CDCA3 at mRNA level was determined by qRT-PCR. Bioinformatics and dual luciferase activity assay were used to predict and detect the targeting relationship between miR-186-5p and CDCA3. NIT-1 cells were transfected with miR-186-5p or si-CDCA3, and treated with high lipid and high glucose, and the effects on cell proliferation and apoptosis were observed. Results High lipid and high glucose significantly reduced the cell viability, protein levels of Ki-67, PCNA and Bcl-2, and mRNA level of miR-186-5p expression in NIT-1 cells, while significantly increased the cell apoptotic rate and Bax protein expression, as well as CDCA3 expression at mRNA and protein levels (P < 0.05). MiR-186-5p negatively regulates CDCA3 as a target. Overexpression of miR-186-5p or knockdown of CDCA3 dramatically improved the cell viability, increased the expression of Ki-67, PCNA, and Bcl-2 at protein level, while remarkably decreased the apoptotic rate and Bax protein expression in NIT-1 cells after the treatment of high lipid and high glucose (P < 0.05). Conclusion ConclusionmiR-186-5p can negatively regulate the expression of CDCA3 gene, and thus promote the proliferation of islet β cells induced by high fat and high glucose and inhibit the apoptosis, so as to protect the islet β cells against the damage induced by high fat and high glucose.

Objective To investigate the expression of long non-coding RNA LINC02163 in hepatocellular carcinoma (HCC) tissues and HCC cell lines, and its effect on the migration and invasion of hepatocellular carcinoma cells. Methods The differential expression level of LINC02163 in 5 HCC cell lines (HuH-7, HCCLM3, MHCC-97H, SNU-182 and SMMC-7721), normal liver cell line (L02) and 60 HCC tissues and paired adjacent tissues was determined by quantitative real-time PCR (qRT-PCR), and the relationship between its expression level and the clinicopathological parameters of HCC patients was analyzed. LipofectamineTM 2000 was used to transfect LINC02163 small interfering RNA (siRNA) into HCC HuH-7 and HCCLM3 cells in order to knockdown the expression. Then the changes of migration and invasion ability of HCC cells after the knock-down of LINC02163 were examined by Transwell assay. Results The expression level of LINC02163 in HCC tissues was significantly higher than that in paired adjacent tissues (P < 0.001), and the level was significantly correlated with TNM stage and microvascular invasion (MVI) in the patients (all P < 0.01). Compared with normal liver cell line (L02), LINC02163 was highly expressed in 5 HCC cell lines (P < 0.001), among which HuH-7 cells had the highest expression level, followed by HCCLM3 cells. LINC02163 knock-down significantly reduced the migration and invasion abilities in HuH-7 and HCCLM3 cells (P < 0.01). Conclusion LINC02163 is up-regulated in HCC tissues and cell lines and promotes the migration and invasion of HCC cells, which may be closely associated with the occurrence and development of HCC.

Participatory approach is useful to clarify local interests, and improve planning activities. This paper aims to evaluate local interests change and make improvements of rural development planning activities as a response. Participatory approaches were used to make rural development planning in 2007. According to the planning activities in 2007, implementation of plans and local developing requirements were tested from local perspective in 2012. Comparing local developing requirements in 2007 and 2012, local interests changes were clarified and used to advise planning activities improvements. Wangzhuang village, Hebei province, China, was chosen as the case study. The results suggest that local preference was helpful to clarify planning goals. Conflicts between different stakeholders’ interests were mainly about planning activities related to local daily life. Local interests showed a fast changeable character in a short term. These interests generally had a stable requirement on agriculture production improvement, while changed in other aspects during local community development. Participatory approach efficiently identified local interests priority and developing requirements change with a low cost. Then advised planning activities improvements consistent supported local sustainable development. We argue that taking planning activities improvements in response to local interests change through participatory approach could efficiently stimulate rural development.

Objective To discuss the role of a multidisciplinary team (MDT) in the diagnosis and treatment of colorectal cancer with liver metastases. Methods A MDT involving specialists from the departments of radiology, pathology, general surgery, hepatobiliary surgery, oncology and radiotherapy participated in the treatment planning and assessment throughout the treatment in a case of colonic cancer with liver metastases. The patient received comprehensive treatments provided by the MDT to maximize the treatment benefits. Results Examination of the patient showed that the metastatic foci in the liver were resectable. After translational treatment and several rounds of multidisciplinary discussions, the patient received surgical resection of the primary and metastatic lesions with postoperative systemic treatments. Follow-up of the patient showed no evidence of disease after chemotherapy, and survival benefits were achieved from the treatments. Conclusion The multidisciplinary approach is capable of providing the patients with colorectal cancer with specific, precise and individualized treatments to maximize the treatment benefits.

Objective To compare the perioperative and postoperative survival outcomes of laparoscopic hepatectomy (LH) and radiofrequency ablation (RFA) in the treatment of recurrent hepatocellular carcinoma (RHCC) in order to provide high-level evidence-based medical evidence for the treatment. Methods From September 2016 to September 2017, a total of 80 RHCC patients were prospectively enrolled and randomly assigned to the LH and RFA groups. A prospective randomized controlled study was used to analyze perioperative factors, overall survival and disease-free survival of patients between the 2 groups, and COX proportional risk model was used to analyze the risk factors for postoperative recurrence. Results According to this interim follow-up analysis, there was no significant difference in the overall survival time between the LH group and the RFA group (19.3±6.8 vs 18.6±6.2 months, P=0.293). The 1- and 2-year overall survival rates were 92.3% and 89.7% in the LH group and 85.4% and 80.5% in the RFA group. There was statistical significant difference in disease-free survival time between the LH group and the RFA group (16.4±8.5 vs 8.3±7.2 months, P=0.000). The 1-year and 2-year disease-free survival rates were 69.2% and 51.3% in LH group, and 26.8% and 22.0% in RFA group. COX proportional risk model analysis showed that the surgical procedures and preoperative alpha fetoprotein (AFP) level were the risk factors for re-recurrence. Conclusion Our interim follow-up analysis shows that, in selective RHCC patients, LH has a better 2-year disease-free survival rate than RFA.

The aim of this work is to determine the thermal storage temperature of a deep thermal reservoir, which has a great significance for the effective utilization of geothermal resources. The temperature of the reservoir was estimated by the cation ratio geothermometer and SiO 2 geothermometer methods. The results indicate that the K–Mg geothermometer is the best method of the cation ratio methods, with the calculated temperature of 108°C. The average value calculated by the SiO 2 method was 107°C. The measured temperature of the GRY1 drilling water sample in the Cangxian arch belt was 108°C. Because the calculated results of the geothermometers were consistent with the measured value of the borehole water, the K–Mg and SiO 2 geothermometers are suitable for the estimation of deep heat storage temperatures.

CO2 electroreduction (CO2 R) operating in acidic media circumvents the problems of carbonate formation and CO2 crossover in neutral/alkaline electrolyzers. Alkali cations have been universally recognized as indispensable components for acidic CO2 R, while they cause the inevitable issue of salt precipitation. It is therefore desirable to realize alkali-cation-free CO2 R in pure acid. However, without alkali cations, stabilizing *CO2 intermediates by catalyst itself at the acidic interface poses as a challenge. Herein, we first demonstrate that a carbon nanotube-supported molecularly dispersed cobalt phthalocyanine (CoPc@CNT) catalyst provides the Co single-atom active site with energetically localized d states to strengthen the adsorbate-surface interactions, which stabilizes *CO2 intermediates at the acidic interface (pH=1). As a result, we realize CO2 conversion to CO in pure acid with a faradaic efficiency of 60 % at pH=2 in flow cell. Furthermore, CO2 is successfully converted in cation exchanged membrane-based electrode assembly with a faradaic efficiency of 73 %. For CoPc@CNT, acidic conditions also promote the intrinsic activity of CO2 R compared to alkaline conditions, since the potential-limiting step, *CO2 to *COOH, is pH-dependent. This work provides a new understanding for the stabilization of reaction intermediates and facilitates the designs of catalysts and devices for acidic CO2 R.

In order to process the hardened face gear,and improve the application of face gear in aeronautics industry,the grinding process of face gear is studied. A worm grinding wheel for grinding process of the face gear is studied in design and dressing method. According to the meshing relationship of face gear,worm grinding wheel and medium gear,the coordinate systems of face gear,worm grinding wheel and medium gear are set up. Combing the relationship between the tooth profile equation and the coordinate transformation and using the enveloping theory,the tooth profile equation of face gear,worm grinding wheel and medium gear are deduced,the processing method of worm grinding wheel and face gear is obtained. Through the numerical computation method,the tooth profile simulation of face gear and grinding wheel is carried out,the 3D model of face gear,worm grinding wheel and medium gear are set up. The approach and principle of dressing are studied,the simulation of dressing process is carried out,and a basis of grinding process of face gear is provided.

In the past several decades, climate change and human activities have influenced hydrological processes, and potentially caused more frequent and extensive flood and drought risks. Therefore, identification and quantification of the driving factors of runoff variation have become a hot research area. This paper used the trend analysis method to show that runoff had a significant downward trend during the past 60 years in the Second Songhua River Basin (SSRB) of Northeast China. The upper, middle, and lower streams of five hydrological stations were selected to analyze the breakpoint of the annual runoff in the past 60 years, and the breakpoints were used to divide the entire study period into two sub-periods (1956–1974 and 1975–2015). Using the water–energy coupling balance method based on Choudhury–Yang equation, the climatic and catchment landscape elasticity coefficient of the annual runoff change was estimated, and attribution analysis of the runoff change was carried out for the Fengman Reservoir and Fuyu stations in SSRB. The change in potential evapotranspiration has a weak effect on the runoff, and change in precipitation and catchment landscape were the leading factors affecting runoff. Impacts of climate change and land cover change were accountable for the runoff decrease by 80% and 11% (Fengman), 17% and 206% (Fuyu) on average, respectively; runoff was more sensitive to climate change in Fengman, and was more sensitive to catchment landscape change in Fuyu. In Fengman, the population was small, owing to the comparatively inhospitable natural conditions, and so human activities were low. However, in Fuyu, human activities were more intensive, and so had more impact on runoff for the Lower Second Songhua River compared to the Upper Second Songhua River.

We describe an apparatus for investigating the excited-state dissociation dynamics of mass-selected ion-molecule clusters by mass-resolving and detecting photofragment-ions and neutrals, in coincidence, using an ultrafast laser operating at high repetition rates. The apparatus comprises a source that generates ion-molecule clusters, a time-of-flight spectrometer, and a mass filter that selects the desired anions, and a linear-plus-quadratic reflectron mass spectrometer that discriminates the fragment anions after the femtosecond laser excites the clusters. The fragment neutrals and anions are then captured by two channeltron detectors. The apparatus performance is tested by measuring the photofragments: I-, CF3I-, and neutrals from photoexcitation of the ion-molecule cluster CF3I·I- using femtosecond UV laser pulses with a wavelength of 266 nm. The experimental results are compared with our ground state and excited state electronic structure calculations as well as the existing results and calculations, with particular attention to the generation mechanism of the anion fragments and dissociation channels of the ion-molecule cluster CF3I·I- in the charge-transfer excited state.