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With the advancement of China’s dual carbon goals， the large-scale integration of new energy sources has exacerbated the supply-demand balance in power systems. The demand response capability of air-conditioning loads is one of the crucial means for addressing this issue. However， the incentive mechanisms for air-conditioning loads participating in demand response in China are still underdeveloped， limiting user engagement in grid interaction. This paper first analyzes the challenges China faces in this area by examining the characteristics of air-conditioning loads and drawing insights from both domestic and international demand response practices. It then categorizes the stages of air-conditioning loads participating in grid flexibility into initiation， transition， and maturity phases， based on the development levels of electricity market mechanisms， key technologies， and user acceptance. For each stage， different demand response incentive mechanisms are proposed， along with specific implementation recommendations tailored to each phase.

In order to provide reference suggestions for selection of materials for the actual underground corrosion environment of a certain oil field，a high-pressure autoclave was used to simulate the CO2 corrosion behavior of N80Q steel pipes prepared by the 25Mn2，1CrRE and 2Cr steel under 90 ℃and 1.0 m/s in the underground corrosive environment of the oil field.Additionally，scanning electron microscopy，energy dispersive spectroscopy and X-ray diffraction were utilized to characterize corrosion product films of three types of steel.Results showed that the three steels mainly exhibited uniform corrosion characteristics at 90 ℃，and the difference in average corrosion rates was not significant.Meanwhile，the corrosion product films consisted of a relatively dense double-layered structure，and their composition were main FeCO3 and a small amount of FeOOH.The research suggested that Fe3C as an anode in the corrosion film could generate FeCO3 and FeOOH，which led to a significant decrease in corrosion rate at 90 ℃.

ObjectiveThis study compares the safety and effectiveness of theta-burst stimulation (TBS) and repetitive transcranial magnetic stimulation (rTMS) for treating treatment-resistant depression (TRD).MethodsWe reviewed randomized controlled trials (RCTs) that evaluated rTMS and TBS in managing TRD. Searches were conducted in PubMed, Embase, the Cochrane Library, and Web of Science for studies published up to July 31, 2024. Data from these studies were analyzed using statistical software.ResultsFive RCTs involving 1,196 patients were included, with 553 receiving rTMS and 663 receiving TBS. The analysis found no significant differences between rTMS and TBS in reducing depression [SMD = -0.07, 95% CI (-0.19, 0.04)] or anxiety [SMD = -0.02, 95% CI (-0.15, 0.11)], nor in side effects like headaches [OR = 1.00, 95% CI (0.72, 1.40)], nausea [OR = 1.42, 95% CI (0.79, 2.54)], or fatigue [OR = 0.87, 95% CI (0.46, 1.64)].ConclusionsBoth rTMS and TBS are similarly effective in reducing depression and anxiety symptoms, with comparable side effect profiles. However, TBS is more time-efficient, with sessions lasting only 192 seconds, making it a cost-effective option for patients. These findings support TBS as a practical treatment choice for TRD.

As new energy sources scale up for integration into urban power grids， there is a growing spatiotemporal mismatch between supply and demand in power systems. This mismatch could gradually undermine the static voltage stability of the power systems， jeopardizing electrical safety. To counter this challenge， a novel method for the optimal allocation of energy storage in urban power grids is proposed， with a special focus on maintaining static voltage stability under a mismatch of supply and demand. The method begins with a characteristic analysis of the mismatch between supply and demand in urban power grids. Assessment indicators for the mismatch in space and time are established. Following this， the number of power flow solutions is analyzed using the discriminant of a quadratic equation based on power flow equations of transmission lines， leading to the introduction of an index for assessing the static voltage stability of urban power grids. Subsequently， an optimal allocation model for energy storage devices is developed by weighting the aforementioned indicators of the spatiotemporal mismatch as well as static voltage stability. Lastly， the effectiveness and superiority of the proposed method are verified through simulation.

The phase transformation temperature of C55E material can be obtained by simulating TTA curve, CCT curve and TTT curve with material simulation software JMatPro. The isothermal quenching process of C55E steel chain plates is formulated by the obtained transformation temperature. The results show that the isothermal quenching process parameters formulated by the material simulation software JMatPro are the quenching temperature of 850 ℃, the isothermal temperature of 310 ℃, and the isothermal time of 25 min. The hardness of the chain plate after isothermal quenching meets the technical requirements, and the strength, fatigue and other properties of the chain are close to the 50CrV material treated by the same process.

This paper summarizes the nursing experience of an elderly patient with third degree scalded in lower limbs during physiotherapy. In the process of nursing and treatment, in addition to routine dressing change treatment and relevant theories of Qi-blood in surgery of Traditional Chinese Medicine, the process of benefiting air temperature Yang and enriching blood and promoting blood circulation throughout was carried out and divided the treatment into two stages, namely, removing the fusty and pus in the early stage, removing the fusty and promoting the muscle in the later stage, and supplemented by traditional Chinese medicine collapse stains to clear heat and detoxify, reduce swelling and remove the degeneration. Interventions based on theories of Traditional Chinese Medicine Qi-blood are conductive to blood sugar control, nutrition care, mental health and the patient's wound healing. (本文总结1例老年患者理疗过程中发生下肢烫伤的治疗和护理经验。在常规换药治疗的同时, 借鉴了中医外科气血相关理论, 将益气温阳, 补血活血贯穿始终, 将治疗分为了两个阶段。前期祛腐提脓, 后期祛腐生肌, 辅以中药溻渍以清热解毒, 消肿祛腐, 积极控制血糖, 加强营养护理, 关注心理健康, 促进创面彻底愈合。)

Due to the complex marine environment, ship engines are under the harsh working conditions of high humidity and high salinity for a long time, which seriously aggravates the frictional wear of engine chains and thus affects the working stability and the fatigue life of engines. Based on this, this study designs the surface textures on the chain pin in three shapes—square, sine and circular. Combining experiments and simulations, the influence of texture shape, area occupancy and depth on the friction and wear resistance is studied in order to provide new ideas and theoretical basis for solving the long-term engine chain wear problem. The results show that the presence of the texture reduces the elemental Cr content of the surface after wear and thus improves the surface wear resistance compared to a smooth no-texture surface. Among the three texture shapes, the sinusoidal texture exhibites the best friction reduction and wear resistance performance, and the highest friction reduction rate of about 31. 9% is achieved under high speed and light load conditions. The sinusoidal texture has the shallowest surface wear marks, and the wear process is mainly micro-motion wear, accompanied by slight adhesive wear.

The Yellow River Delta adjacent to the Bohai Sea is located in the monsoon region of northern China, which is sensitive to global climate change. The core data of KY-01 borehole in the Yellow River Delta and the published records were used to reconstruct the climate environment. Based on the analysis of carbonate content, magnetic susceptibility, Ostracoda, foraminifera, sporopollenin and AMS 14C dating on the KY-01 borehole sediment core, the evolution of both the climate and sedimentary environment has been discussed. The results show that: 7656–4145 cal.aBP, seawater moved toward the land surface and the climate was generally warm and humid, when there were small-scale extreme climate fluctuations; 4145–2544 cal.aBP, transgression and recession occurred, the climate changed from warm-wet to dry-cold and there were small-scale extreme climatic events; and 2544 cal.aBP–1855 AD, the sea level was relatively low, transgression and retreat alternately occurred, the climate was drier and colder than the previous stage and the warming and cooling alternated. During the middle Holocene, cold-dry events occurred between 5737–5422 and 4451–4081 cal.aBP, which is consistent with both Chinese and worldwide climate records. HIGHLIGHTS Reconstruction of Holocene environment in the Yellow River Delta using multi-proxy indices.; Two extreme climate events in the study area since Holocene were analyzed.; Compared with the Holocene climate and environmental changes in Shandong Province.;

In order to explore the influence of the opening of the movable guide vane on the flow and pressure pulsation in the draft tube of the Francis turbine,the steady and unsteady numerical simulations were carried out by establishing a three-dimensional full-flow channel model of a Francis turbine in a power station in southwest China,and the flow characteristics and pressure pulsation of the draft tube of the Francis turbine under different guide vane opening of the rated head were studied.The results show that with the increase in guide vane opening,obvious alternating vortices appear in the straight cone section of the draft tube,which cause low-frequency pressure pulsation in the draft tube.The uniformity of pressure and velocity distribution in the draft tube gradually deteriorates,and the main frequency amplitude of pressure pulsation at the elbow section of the draft tube increases first and then decreases.The vortex zone of the draft tube causes the pressure pulsation of low frequency and high amplitude in the draft tube.

The power curves of the oversized chains over 56B are deficiency in the ISO or GB standard. All the parameters of the oversized chains remain to be tested. A test machine based on the principle of closed power flow is developed for the oversized chains testing. The basic composition，technical parameters and testing range are introduced. The characteristics of the oversized chains under the condition of pressure spray oil lubrication over 56B，such as wearability，power capacity and other characteristics of running in different speed and load can be tested，the technical data for the chains developers is provided.

Environmental conditions can significantly affect the performance of photovoltaic (PV) hydrogen production systems, resulting in fluctuations in PV output and suboptimal hydrogen production. In order to solve these problems, a voltage stabilization control based approach has been implemented for a photovoltaic integrated hydrogen production system, which is based on an existing hydrogen production model coupled to PV storage. The aim of this approach is to enhance system stability, improve the quality of photovoltaic power generation, and optimize hydrogen production. The strategy includes maximum power point tracking (MPPT) control for the PV system, as well as coordinated control of the electrochemical energy storage system to ensure stable bus voltage and efficient use of solar resources. The effectiveness of this control strategy was demonstrated by simulation.

Taking a low-speed two-stroke marine diesel engine bedplate as the research object.The main bearing seat（material ZG200-400） crack growth rate was tested,and the fatigue crack growth rate and the Paris formula of the stable expansion section were obtained.The three-dimensional crack propagation life analysis model of the main bearing seat was established by the sub-model method.The real boundary conditions of the main bearing seat was obtained by combining with the analysis results of the alternating stress of the bedplate under the actual operating conditions of the engine（360 degree crank angles）.The crack growth life of the main bearing seat with initial crack was calculated.The analysis results show that the crack growth life is less than that of the low-speed two-stroke marine diesel engine overhaul inspection interval.The research results of the thesis provide an reference for the damage tolerance in design engineering application.

BACKGROUND The industry criteria of determination of soil cation exchange capacity (CEC) (LY/T1243-1999)uses centrifugal separation combined with manual distillation and titration, which is complex and time consuming. OBJECTIVES Determination of soil cation exchange capacity by automatic Kjeldahl analyzer after oscillating exchange and vacuum filtration. METHODS The acidic and neutral soils were treated with ammonium acetate, the calcareous soil was treated with ammonium chloride-ammonium acetate, and the cations were quickly exchanged and cleaned by shaking and by using suction filtration equipment, and adsorbed by a fully automatic Kjeldahl analyzer. The ammonium ion was measured to calculate the CEC value. RESULTS The experimental results show that, under the optimized oscillation and distillation, concentration of titration acid and ratio of indicator conditions, the analysis of one batch sample (100 pieces) only takes 12 hours. Compared with traditional methods, the detection time is shortened by nearly 80%. The results of national standard materials determined by the proposed method are in accordance with the certified values, the relative standard deviation is less than 1.5% (n=5). CONCLUSIONS The method eliminates multiple centrifugation operations, solves the problem of low component loss and CEC measurement value deviations, and improves detection efficiency and accuracy. This method has a lower cost than the forestry standard method, and has high operability and is suitable for analysis of large-scale soil samples such as environmental quality assessment and regional soil sampling surveys.

The effect of sodium tungstate in insulation coating solution of grain-oriented silicon steel on the microstructure and properties of the prepared phosphate insulation coating was investigated by using scanning electron microscopy (SEM), Epstein square,insulating resistance tester and Fourier transform infrared spectrum (FTIR) et al. The results show that, with the gradually increasing content of sodium tungstate in the coating solution, the wetting angle between the coating solution and the grain-oriented silicon steel substrate first decreases and then increases; the interlamination resistance, lamination factor and magnetism induction intensity of grain-oriented silicon steel first increase and then decrease, the iron loss first decreases and then increases. When the sodium tungstate content is 2.0%(mass fraction), the coating solution shows the best wettability on the grain-oriented silicon steel substrate, the wetting angle is 39.3°; at the same time, the formed insulation coating is dense and smooth, there is a diffusion area about 0.8μm at the junction between the insulation coating and the magnesium silicate bottom layer, furthermore, the humidity resistance of the insulation coating is not significantly changed; the interlamination resistance, lamination factor, magnetism induction intensity and iron loss of grain-oriented silicon steel reach the optimal values, which are 14073Ω·mm2, 97.0%, 1.893T and 1.051W·kg-1, respectively.

C17H14O3, monoclinic, C2/c (no. 15), a = 17.373(4) Å, b = 7.8290(16) Å, c = 19.781(4) Å, β = 93.62(3)°, V = 2685.2(9) Å3, Z = 8, Rgt(F) = 0.0447, wRref(F2) = 0.1313, T = 293(2) K.