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It is difficult to solve the binding force of motion pairs of over-constrained mechanisms. This study attempted to decompose the constraint term in the d'Alembert principle into two parts, static constraint and dynamic constraint. The static constraint under constraint conditions and the dynamic constraint of the equilibrium inertial force were obtained separately, and the total constraint force of the example was solved through the superposition of the two. Taking three pairs of uniform transmission rod space RCCR mechanism as the research object, the binding force was solved by the above method, and the solution results were compared with the dynamic simulation results. The results show a good consistency.

【Objective】 Change in soil water content is not only an indicator of water stresses used for irrigation management but also controls biogeochemical processes in soil. In this paper, we study the feasibility of using thermal infrared imaging to estimate soil moisture dynamics. 【Method】 The experiment was conducted in July-August 2023 in a walnut orchard in Xinjiang. Thermal infrared images of the walnut canopy were measured continuously using a thermal infrared camera. Based on the HSV color space of the images, an improved K-means segmentation algorithm was proposed to analyze the change in canopy temperature. We also measured air temperature and humidity, illuminance, wind speed, atmospheric CO2, and soil water content in the 0-80 cm soil layer, from which we proposed an inversion model to estimate soil water dynamics. 【Result】 The improved K-means algorithm increased the accuracy from 82.34% to 94.55%, and the errors between the canopy temperature acquired from the images and the measured canopy temperature were in the range of 0 to 1.0. The infrared imaging method was most accurate between14:00 pm to 16:00 pm. Our results showed that the walnut roots were most active in taking up water from the 40-60 cm soil layer 50-60 cm away horizons from the tree truck. Canopy temperature, air temperature and relative humidity, and atmospheric CO2 concentration were correlated with soil water content at significant levels; they can thus be used to estimate soil water dynamics, with a coefficient of determination of R2=0.86 and p

In this paper, 66 samples belonging to 12 varieties of domestic high-gluten wheat in 2021 were collected, and their physicochemical, rheological and bread sensory properties were analyzed. The results of the main component analysis showed that the total sensory score of bread had a strong correlation with gluten index, maximum tensile resistance, mixing time, stretching area and stabilization time, etc. At the same time, the screening of wheat varieties with high similarity through cluster analysis could play a key guiding role in the development and maintenance of production stability of baking special flour. Comparing the fitting quality of the bread total sensory score prediction model established by the three methods of stepwise regression, partial least squares and neural network model, the model built using artificial neural network was significantly better than other models. Using neural network models, the baking characteristics of different varieties of wheat could be quickly predicted, ensuring product stability, while also facilitating the development of more targeted baking special flours.

Surface modification of poly(benzoxazole-imide) (PI) film was carried out by means of oxygen plasma treatment. A flexible copper clad laminate (FCCL) was fabricated using Ni-Cr ion implantation and electro-Cu plating process. Controlling the constant pressure, the effects of such treatment conditions as power and time were systematically investigated on the surface roughness, chemical composition and interface adhesion with Cu. It is found that the optical parameters for production of FCCL with excellent adhesion and solder resistance are 50 W/5 min and 100 W/10 min, respectively. Suitable roughness, reactive radical with high content pendent oxygen group, and metal-oxazole complex help to endow exceptional adhesive property to the interface of PI/Cu. And the peel strength of FCCL prepared from PI film with such modified surface rises by 60%.

Sorafenib resistance has been a major factor limiting its clinical use as a targeted drug in liver cancer. The present study aimed to investigate whether cryptotanshinone can enhance the sensitivity of liver cancer and reduce the resistance to sorafenib.

[Purpose/significance] In the era of mobile internet, people expect to acquire knowledge services through mobile terminals, and the mobile institutional repository is an important carrier and channel. As an office tool for internal communication, enterprise Wechat gradually integrates into the Wechat ecosystem and is applied by more units and organizations. [Method/process] Taking the construction of mobile institutional repository of China Academy of Information and Communications Technology (hereinafter referred to as “CAICT”) as an example, this paper analysed the application requirement, put forward the construction mode of “Enterprise Wechat + Web APP”, introduced in detail the process of system design and realization of main functions, and analysed the system effect and experience summary. [Result/conclusion] Starting from individual practice, this paper explores the mode of "Enterprise Wechat + Web APP" to build Mobile Institutional Repository, which is fast release, easy to use, high efficiency, low cost, universal and replicable, and has certain reference significance for other knowledge service organizations.

Graphene, as a rising star in materials science, is intensively studied in Li-ion batteries and supercapacitors, owing to its unique structure and excellent properties. The research status of the application of graphene in energy storage field was disscussed and the future development trend was predicted, and therefore to enhance the understanding of the structure-performance relationship of graphene and also the application of graphene in this field. Firstly, the application of graphene in cathode and anode of Li-ion battery, and the application of graphene in electrical double-layer capacitor and pseudo-capacitor were introduced. Secondly, the challenges of graphene in electrical double-layer capacitor were discussed and the ideal structure of graphene applied to electrical double-layer capacitor was proposed. Finally, the "three steps" to realize the commercial application of graphene-based electrical double-layer capacitor were put forward.

The bulky electrolytic capacitor is conventionally used to curb the output voltage ripple of output DC-link in the front-end PFC AC/DC converter, which is applied for the on-board charger of the electrical vehicle. Due to the drawbacks of electrolytic capacitor, such as the short lifetime, susceptibility to temperature and other reasons, the reliability and usage cycle of on-board charger are reduced, even leading to the system breakdown. In order to decline the output voltage ripple in the output DC-link, the PFC AC/DC converter paralleled with power decoupling circuit at the output side is proposed, ensuring safe and reliable operation in the on-board charger. It contributes to diminish the volume of output filtering capacitor sharply and utilize the excellent film capacitor instead of the electrolytic capacitor. In this paper, the mathematical model of power decoupling circuit is established based on the detailed analysis of the circuit operation. Besides, the improved PR(Proportional Resonant) controller is designed to dominate the power decoupling circuit. In order to improve the control performance and robustness, the model-free nonlinear power control strategy is implemented to the PFC AC/DC converter. Based on the aforementioned researches, a 700 W experiment prototype is developed. The feasibility and efficiency of the proposed method are validated by the DSPACE 1007 test platform.

To overcome the shortcomings of the full-bridge DC/DC converter topology for on-board charger, an improved phase-shifted full-bridge converter topology is suggested，and its working principle is analyzed when it operates in the discontinuous current mode(DCM), the key components parameters design is researched in the condition of 2 kW operating conditions, and then, the switching element average model method is proposed to set up the ideal small-signal model of improved phase-shifted full-bridge converter operating in DCM, moreover, the sweep frequency method is used to validate the rationality of modeling methods and established models.

Using bushings with great stiffness coefficient to replace the rigid constraints,the dynamics simulation of the over-constrained spatial RCCR mechanism with three pairs of force transmitting rods under conditions approaching rigidity is achieved.The simulation experiment targeting different structural parameters and resistance moment,the variation discipline of transmitted force is obtained,the cosine function type of constraint component Fz is fitted out,the estimation formula of Fz amplitude is summed.

The deformation compatibility equation is built on the basis of the flexible treatment of the forcing pair,and the static binding force of forcing pairs of three pair bars space RCCR mechanism is solved under the condition of close to rigid body.The result is more concise and closing to the ideal state compared with that on the basis of the flexible treatment of the forcing bars.

ObjectivesThe lithium-ion capacitor (LIC) composite cathode materials with both high mass activity and high volume activity were designed.MethodsBy scanning electron microscope, transmission electron microscope, Kanta fully automatic specific surface and pore size analyzer, and four-probe tester, the micromorphology, stacking mode, contact mode and interface characteristics between particles were analyzed for the impact of conductivity and electrical properties of composite electrodes.ResultsMesoporous activated carbon (MC) and monodisperse graphene/single-walled carbon nanotube hybrid (GNH) were mixed, followed by compressing tightly to prepare the lithium-ion capacitor cathode material. GNH were uniformly wrapped around the surface of MC particles with face-to-face connection, which increases the contact area. Then, the even 3D conductive network constructed by GNH among the individual MC particles provided high electrical conductivity and accelerated electron conduction. In addition, GNH were located at the high ion concentration side due to their exohedral surface structure. Meanwhile, a contact potential difference effect existed between GNH (the easy conductive one) and MC (the poor conductive one). This produced rapid ion and electron dual transport channels at the interface between GNH and MC, and boosted ion diffusion in the porous structure inside MC particles. It will help avoid the loss of capacity from slow ion diffusion at higher current densities.ConclusionsThe addition of 5% GNH brings about outstanding rate performance, and higher mass and volumetric energy density, but does not reduce the packing density.

Nano-zirconium carbide precursor was prepared by hydrothermal method. Nanometer zirconium carbide powder was prepared by carbothermal reduction reaction. The Gibbs free energy and enthalpy change of carbothermic reduction of zirconia were calculated by thermodynamic method. The reaction temperature and reaction mechanism of nanometer zirconia were calculated. The energy and phase changes during the reaction were studied by thermogravimetry and X-ray diffraction. Microstructure observation showed that the precursor was composed of multiple zirconia structures wrapped by a layer of amorphous carbon. This unique structure effectively prevents the agglomeration of the powder and ensures the dispersion of the prepared zirconia. This structure also ensures the dispersion of zirconium carbide powder. Zirconium carbide powder has uniform size and particle size of about 50 nm. Gibbs free energy calculation results show that when the temperature reaches 1656.56 °C, zirconia reacts with C to form CO and ZrC. As the temperature rises, ZrO2 reacts with CO to form CO2 and ZrC. The results of TG-DSC experiments show that the carbothermal reduction reaction starts at about 1100 °C and reaches its peak at 1418 °C. XRD analysis confirmed that ZrC appeared when the temperature reached 1450 °C, and the transformation was basically complete when the temperature exceeded 1600 °C.

In this case report, a 53-year-old woman was diagnosed with severe NE after receiving chemotherapy for breast cancer. The patient with breast cancer was treated with a single cycle of docetaxel (140 mg) + epirubicin (130 mg) + cyclophosphamide (0.9 g) chemotherapy. However, the woman presented with symptoms of fatigue and diarrhea 5 days later accompanied with severe neutropenia according to the routine blood test. The computed tomography examination displayed the thickening and swelling of the colorectal wall. After the diagnosis of NE, the woman received antibiotics and supportive treatment, but her symptoms were not improved. The Chinese herbal medicine (CHM) diagnostic pattern was then designed for the patient. The patient was administered with two CHM decoctions. One decoction contained 24 kinds of herbal materials, and the other one was called pure ginseng decoction. These two decoctions were administered to the patient 2 or 3 times per day to tonify the spleen, nourish Qi and blood, and remove phlegm and damp heat symptoms. After the CHM treatment lasting for 10 days, the symptoms of the patient were improved, and she was discharged. In conclusion, CHM treatment played an indispensable role in curing the woman with chemotherapy-induced NE.

The long period operation at 45 ℃ and 3 V of the mesoporous carbon-ionic liquid-carbon covered aluminum foam based electrical double layer capacitor was studied. The composite electrode sheet was formed by embedding mesoporous carbon with carbon-coated aluminum foam, and the 3 cm×5 cm pouch was composed of EMIBF4 as electrolyte. The operation law of charge and discharge was studied at 45 ℃ and 3 V for 1 500 h. It is found that the internal resistance change rate is about 10%, and the capacitance retention rate is as high as 98%, both of which are far better than those of organic liquid-based electrical double layer capacitor at 2.7 V and 65 ℃. The gas generation of pouches at 2.7 V/65 ℃ and 3 V/45 ℃ was compared. It is proved that the soft package of mesoporous carbon-ionic liquid-carbon-coated aluminum foam based electrical double layer capacitor can work stably at 3 V, 45 ℃ for 1 500 h. It provides a solid foundation for further promoting the application of ionic liquid-based electrical double layer capacitor.

The development of renewable energy is one of the most important guarantees to achieve carbon peak and carbon neutrality. However, the instability of solar energy, wind energy and other new energy sources has shown higher requirements on energy characteristic and power characteristic of energy storage devices. This paper firstly discussed the technical characteristics of traditional lithium-ion batteries and supercapacitors, and put forward the necessity of developing battery-capacitors technology under the new grid energy storage requirements. Then, the technical development trend of key materials for battery-capacitors was discussed in detail from three aspects: the improvement of cathode materials, improvement of anode materials, and innovation of electrode sheet structures, current collectors and electrode tabs. Finally, the three key elements of energy storage devices and their “two-in-one” or “three-in-one” effects were proposed to meet the diversified demands of cost, safety, power characteristic and energy characteristic, and the development trend of battery-capacitors was prospected.

The nano-sized ZrO2 reinforced Mo alloys were prepared by hydrothermal synthesis and subsequent sintering. During preparation, the nano-sized ZrO2 particles were added into the Mo powder via hydrothermal synthesis. This work investigated the differences in mechanical properties and microstructures of the Mo-ZrO2 alloys prepared by hydrothermal synthesis and the other traditional method. As the amount of ZrO2 particles increased, the grain size of the Mo powders reduced obviously. The grains were refined obviously after sintering. The ZrO2 particles added by hydrothermal synthesis can effectively restrain the growth of grains and improve mechanical properties such as strength and hardness.

Mo-0.5Ti and Mo-0.1Zr alloys were prepared by powder metallurgy. In Mo-0.5Ti and Mo-0.1Zr alloys, there appears the second-phase particles of Ti2O3 and ZrO2 respectively, each of which can effectively prevent the dislocation activity in the process of plastic deformation. The addition of Zr can increase the strength of molybdenum alloys. Meanwhile, the ZrO2 formed from the alloy element Zr can refine the grains of molybdenum alloys to improve the recrystallization plasticity. After annealing, the tensile strength decreases while the plasticity greatly increases compared to the annealed Mo-0.5Ti and Mo-0.1Zr alloys. With the increase of annealing temperature, both the tensile strength and plasticity of Mo-0.5Ti and Mo-0.1Zr alloys decrease. Compared with pure Mo, after annealing the properties of the Mo-0.5Ti alloy and the plasticity of the Mo-0.1Zr alloy significantly increases.

The cause of action represents the nature of the legal relationships involved in the case.A scientific and rational choice of the cause of action will facilitate the correct application of laws and enable the courts to perform classification management of cases.Cause of action prediction aims to endow computers with the ability to automatically predict the cause category based on the textual case description.Due to the small number of the samples of low-frequency categories and the difficulty of learning effective features,previous methods usually filters out the samples of low-frequency category in data preprocessing.However,in the problem of predicting the cause of action,the key challenge is how to make an accurate prediction for the cases of low-frequency cause categories.To solve this problem,in this paper,we propose a novel hierarchical learning method based on unbalanced samples for predicting cause of action.Firstly,all causes are divided into the first-level and second-level causes according to their inherent hierarchical structure.Then,the tailed ones in second-level causes can be merged into a new first-level category with sufficient samples,and the hierarchical learning is applied to realize the prediction of cause of action.Finally,we refine the loss function to alleviate the problem of data imbalance.Experimental results show that the proposed method is significantly superior over the baseline methods,leading to an improvement of 4.81% in terms of accuracy.Also,we verify the benefits of introducing the hierarchical learning as well as refining the loss function for unbalanced data.

Restraining algal growth by algaecide has been studied by many researchers, but the dosing time has not yet been studied. In this study, we examined the appropriate dosing time of algaecide through a series of experiments. In the experiments, the pH value of water is significantly affected by Microcystis aeruginosa, and the variation of the pH value is in favor of the growth of the alga. Therefore, using acid algaecide in the period with maximum pH values, i.e., the stable phase, would change the acidity-alkalinity of the water significantly, land would negatively affect algal growth. Acid algaecide does not eliminate the alga effectively if the acid algaecide is dosed in the logarithmic growth phase. Using acid algaecide in the decline phase after algal bloom not only is unfavorable for eliminating the alga, but also prolongs the decline phase, and even brings about next larger algal bloom.