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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.

Objectives: To examine the correlation of apparent diffusion coefficient (ADC), diffusion weighted imaging (DWI), and T1 contrast enhanced (T1-CE) with Ki-67 in primary central nervous system lymphomas (PCNSL). And to assess the diagnostic performance of MRI radiomics-based machine-learning algorithms in differentiating the high proliferation and low proliferation groups of PCNSL. Methods: 83 patients with PCNSL were included in this retrospective study. ADC, DWI and T1-CE sequences were collected and their correlation with Ki-67 was examined using Spearman's correlation analysis. The Kaplan-Meier method and log-rank test were used to compare the survival rates of the high proliferation and low proliferation groups. The radiomics features were extracted respectively, and the features were screened by machine learning algorithm and statistical method. Radiomics models of seven different sequence permutations were constructed. The area under the receiver operating characteristic curve (ROC AUC) was used to evaluate the predictive performance of all models. DeLong test was utilized to compare the differences of models. Results: Relative mean apparent diffusion coefficient (rADCmean) (ρ=-0.354, p = 0.019), relative mean diffusion weighted imaging (rDWImean) (b = 1000) (ρ = 0.273, p = 0.013) and relative mean T1 contrast enhancement (rT1-CEmean) (ρ = 0.385, p = 0.001) was significantly correlated with Ki-67. Interobserver agreements between the two radiologists were almost perfect for all parameters (rADCmean ICC = 0.978, 95%CI 0.966–0.986; rDWImean (b = 1000) ICC = 0.931, 95% CI 0.895–0.955; rT1-CEmean ICC = 0.969, 95% CI 0.953–0.980). The differences in PFS (p = 0.016) and OS (p = 0.014) between the low and high proliferation groups were statistically significant. The best prediction model in our study used a combination of ADC, DWI, and T1-CE achieving the highest AUC of 0.869, while the second ranked model used ADC and DWI, achieving an AUC of 0.828. Conclusion: rDWImean, rADCmean and rT1-CEmean were correlated with Ki-67. The radiomics model based on MRI sequences combined is promising to distinguish low proliferation PCNSL from high proliferation PCNSL. [ABSTRACT FROM AUTHOR]

It is vital to measure combustion temperature to define combustion models accurately. For single fuel particles in powder-fueled ramjets, their size distribution ranges from submicron to submillimeter, and their burn time is short to millisecond order. Moreover, the radiation intensity of different types of fuel particles significantly oscillated with several orders of magnitude. Current temperature measurement technology is facing this challenge. This paper proposes a highly spatiotemporal resolved pyrometry to measure the combustion temperature of fuel particles by coupling single-point photomultiplier tube (PMT)-based and two-dimensional complementary metal oxide semiconductor (CMOS)-based photoelectric devices. Both the offline calibration by blackbody furnace and online calibration by standard lamp confirmed the measurement accuracy of the pyrometry. Then, the pyrometry was used to measure the combustion temperature of fuel particles including micro-Al, nano-Al, micro-Mg, nano-B, and micro-B4C. The temperature evolution and distribution of burning fuel particles were complementarily obtained, especially the interfacial flame temperature near the particle surface. Based on the obtained combustion temperature, the combustion characteristics and the energy release efficiencies among these fuels were evaluated and compared in detail, which are helpful to recognize, in depth, the combustion behavior and reveal the combustion mechanism of fuel particles in powder-fueled ramjets. [ABSTRACT FROM AUTHOR]

As an important physiological indicator, wheat canopy temperature (CT) can be observed after flowering in an attempt to predict wheat yield and quality. However, the relationship between CT and wheat yield and quality is not clear. In this study, the CT, photosynthetic rate (Pn), filling rate, wheat yield, and wheat quality of 68 wheat lines were measured, in an attempt to establish a connection between CT and yield and quality and accelerate the selection of new varieties. This experiment used an infrared imaging camera to measure the CT of wheat materials planted in the field in 2022. Twenty materials with significant temperature differences were selected for planting in 2023. By comparing the temperature trends in 2022 and 2023, it is believed that materials 4 and 13 were cold-type materials, while materials 3 and 11 were warm-type materials. The main grain filling period of cold-type materials occurs in the middle and late stages of the grain filling period and the Pn and the thousand-grain weights of cold-type materials were higher than those of warm-type materials. Similarly, under continuous rainy conditions, cold-type materials had a higher protein and wet gluten contents, while warm-type materials had higher sedimentation values and shorter formation times. [ABSTRACT FROM AUTHOR]

Climate change has led to significant changes in water and heat conditions in crop production areas, which have in turn affected the spring maize growth and yield. This study analyzed the spatiotemporal variation characteristics of the water and heat conditions, such as the growth degree-day (GDD), killing degree-day (KDD), sunshine hours (SD), effective precipitation (Pe), and irrigation water requirement (IR), of spring maize in Inner Mongolia based on data from 50 meteorological stations. The relationship between hydrothermal conditions and yield was revealed using methods that included stepwise regression analysis. The results showed that the GDD during the spring maize growth period ranged from 513 to 2011 °C, with high-value areas concentrated in western and southeastern regions of Inner Mongolia. The GDD showed an increasing trend during all the growth periods. High-KDD areas were mainly distributed in the Alxa League region in western Inner Mongolia, and the KDD showed an increasing trend during all periods except the rapid fertility period. The spatial distribution of the SD was consistent with that of the GDD, and the SD values for each reproductive period showed a decreasing trend. The average Pe and IR values in the last 60 years were 111 mm and 386 mm, respectively, and showed opposite spatial distribution trends. The overall Pe trend was decreasing and that of the IR was increasing, which will aggravate future water resource consumption in the region. Stepwise regression analysis showed that the Pe was the main factor affecting the spring maize yield. Overall, the spring maize fertility period in various regions of Inner Mongolia was extremely uneven in terms of the hydrothermal conditions. This study provides a basis for the regional spatial spring maize layout and the sustainable use of water and heat resources in the region. [ABSTRACT FROM AUTHOR]

Freshwater fungi consist of a highly diverse group of organisms in freshwater habitats worldwide. During a survey of fungal diversity in freshwater habitats across different regions of Jiangxi Province, China, four freshwater fungi were collected. To study their phylogenetic relationships, the internal transcribed spacer (ITS1-5.8S-ITS2), large subunit (28S, LSU), small subunit (18S, SSU), and RNA polymerase II subunit (RPB2) genes were selected for phylogenetic analyses. Based on morphology coupled with phylogenetic analysis, these strains were confirmed to belong to Phaeoisaria, Pleurothecium, and Pseudodactylaria. Among them, three fungi were confirmed as the new species, namely, Pleurothecium lignicola (Pleurotheciaceae), Pseudodactylaria jiangxiensis (Pseudodactylariaceae), and Ps. lignicola (Pseudodactylariaceae). One species was identified as Phaeoisaria filiformis (Pleurotheciaceae), a new record of this species in China. All species were compared with other similar species, and detailed descriptions, illustrations, and phylogenetic data were provided. [ABSTRACT FROM AUTHOR]

In situ microfibril structure can significantly improve the mechanical properties of incompatible blends. In this work, the in situ microfibrils were constructed in isotactic polypropylene/polylactic acid (iPP/PLA) blends by direct injection molding process, and the effect of viscosity ratio on the morphology was systematically analyzed. The results of scanning electron microscope and rheology show that the viscosity ratio plays a decisive role in the formation of in situ microfibrils. When the viscosity ratio of PLA/iPP is near 1, deformation and microfibrillation of PLA particles can be conducted due to the larger and more uniform distributed PLA domains as well as stronger viscous drag forces. However, irregular cylinders are observed when the viscosity ratio is far lower than 1. The poor deformation ability of PLA particles should be attributed to the much smaller size and weaker viscous drag forces. The well-defined PLA microfibrils are conducive to avoid damage at the interface, and play a significant role in the enhancement of tensile strength and modulus. This work can simplify the traditional preparation process, construct in situ microfibrils directly by using conventional melt processing techniques and provide a new ideal for the high performance of incompatible polymer blends., INTRODUCTION The properties of incompatible blends mainly depend on the properties of each component, the interfacial adhesion between components and, more importantly, the microscopic phase morphology formed during melting process [...]