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[Objective] Land use change is one of the important driving forces for increasing carbon emissions and the environmental quality. The temporal and spatial pattern changes and effects of land use carbon emissions were analyzed in order to provide a theoretical basis for the formulation of low-carbon development strategies. [Methods] The internal relationships between land use changes and carbon emissions, carbon emission intensity and ecological effect were determined based on gray theory and ecological carrying coefficient by using land use and energy consumption data for 22 counties in Ningxia Hui Autonomous Region from 1980 to 2020. [Results] ① There was a close correlation between carbon emission changes and land use changes. The correlation between construction land and carbon emissions was the largest (0.95). ② Net carbon emissions of land use types in Ningxia increased by 5.24×107 t and had a growth rate of 625.43% from 1980 to 2020. This pattern was associated with significant increases in construction land area and carbon emissions (average annual rates of 4.42% and 2385.85%, respectively) during the period of 1980—2020. Additionally, grassland area decreased by 2.95×105 hm2, and the carbon sink decreased by 5.80×104 t. Forest land was the main carbon sink, accounting for more than 75% of the carbon sink in 2020, and increased with increasing area. ③ The carbon emission intensity of land use in Ningxia increased at an average annual rate of 0.25 t/hm2 from 1980 to 2020, and the coverage area of moderate and above grades increased gradually. A spatial distribution pattern of carbon emission intensity for cities along the Yellow River developed higher than observed for the central and southern regions. ④ Due to differences in county economic level and natural environment, the spatial differences in ecological support coefficients of carbon emissions for the 22 counties in Ningxia was obvious, and the distribution pattern of carbon sink capacity was weak in the north and strong in the south. [Conclusion] The carbon emission intensity of land use in Ningxia gradually increased from 1980 to 2020. The carbon ecological capacity of counties along the Yellow River in the north gradually decreased. The carbon ecological capacity of counties in the central and southern regions increased, but the pressure of emission reduction was greater. We recommend optimizing the spatial pattern of construction land, increasing the area of mixed forests, and enhancing forest carbon sink capacity.

With the development of new technologies in power system and the implementation of flexible policies such as demand response, traditional power consumers are gradually turning into prosumers, and their power consumption habits are also evolving and changing. In this paper, the features of power users and the potential value of massive power consumption data can be described and fully utilized by portrait technology. A method of power users' behavior portrait based on information gain and Spearman correlation coefficient is proposed. Firstly, k-means clustering algorithm based on gap statistic is used to analyze the power users' consumption data. Then, considering the effectiveness and redundancy of the feature set, the adaptability evaluation coefficient is introduced. On this basis, the optimal feature subset is obtained by genetic algorithm. Furthermore, quantitative analysis is implemented to characterize the portrait of power users. Several case studies are presented to demonstrate the effectiveness of the proposed method.

With the increase of the turbine inlet temperature of gas engines, the widely used Y2O3 partially stabilized ZrO2（YSZ）thermal barrier coatings (TBCs) have been unable to meet the requirements, and new generation TBCs that can survive ultra high-temperatures are urgently needed. Among many TBC candidates, GdPO4 has a great application prospect. In this study, GdPO4/YSZ TBCs were prepared by air plasma spraying, and the effects of preparation parameters, especially spraying power on the phase composition, surface morphology, microstructure and bond strength of GdPO4 coatings were investigated. The results show that the P loss takes place during spraying, and both GdPO4 and Gd3PO7 phases are detectable in the final topcoats, the content of the latter decreases by reducing the spraying power. The GdPO4 coating microstructure is mainly composed of piles of fully melted spray particles, among which there is porous micro-zone consisting of unmelted particles. With the decrease of the spraying power, the content of the micro-zone increases, and the coating thickness significantly decreases. The bonding strength of GdPO4/YSZ TBCs decreases with the decrease of spraying power, which is mainly because the cohesion of coating decreases with the increase of unmelted micro-zone. Therefore, low spraying power is not beneficial to the coating bonding strength.

Traction robot conveying technology is efficient in horizontal well logging. Auto-centralizer is an assistant support to bear the weight of robot and center the robot in casing while logging. The mechanical model for an auto-centralizer with four pair of bias arms was built based on spring-lever mechanism. ADAMS (Automatic Dynamic Analysis of Mechanical Systems) was applied to analyze the sensitiveness coefficient of structural parameters and spring force, thus optimizing the structural parameters. Consequently, a simulation model was built based on the optimization result, and a simulation study was carried out on the mechanical properties and dynamic performance with the ADAMS mechanics system modeling and simulation module. The results implied that the original structure had a disadvantage while traversing obstacles. Further studies indicated that the coupling between the pair arms adopted hinge joint, which couldn't form a closed triangle of force while traversing obstacles. We have employed an improved structure by adding a connecting lever to eliminate the constraint between the arms. Contrast experiments show that the new structure avoids bearing the load with one side and has less shock while traversing obstacles, thus improving smoothness of movement for the traction robot. 摘要: 牵引机器人输送技术是油田水平井测试中仪器输送的有效手段, 自动定心机构是牵引机器人的辅助支撑, 用来承受牵引机器人的自重, 使机器人始终保持与管道同轴。通过对弹簧蓄能轮式定心机构结构形式与工作原理的研究, 建立了偏置式4对臂自动定心机构的力学模型; 利用ADAMS (Automatic Dynamic Analysis of Mechanical Systems)的优化工具, 分析了各结构参数与弹簧力的敏感系数, 完成了结构参数的优化; 根据优化结果建立了仿真模型, 利用ADAMS的机械系统建模与仿真模块对其力学特性及动态性能进行了仿真研究, 发现越障时结构上存在缺陷, 由于两臂之间采用铰接, 越障时不能形成独立的力封闭三角形。据此提出了改进方案, 通过增加连杆来消除两臂间的制约关系。改进后的模型在越障时避免了单侧轮受力, 减少了冲击, 提高了机器人运动的平稳性。 Key words: horizontal well, traction robot, auto-centralizer, dynamic simulation

In order to improve the degree of baking automation of dryer, and realize the feeding and hot processing of sunflower seeds, a control system for double layer sunflower seeds dryer with PLC as the core processor and touch screen as the man-machine interface was designed. The control of the double layer sunflower seeds dryer was realized by connection with the actuating and sensing components in combination with electric design. The system can realize the functions such as setting and adjustment of process parameters, monitoring of running state, recording of historical data. The average score of subjective evaluation of quality and efficiency is 43.74 points, which is much higher than 38.26 points of the single-layer oven. The experiment shows that the system is simple and its running is stable, and the subjective score is improved by 11% compared with the comparison equipment. It is suitable for the control of double layer sunflower seeds dryer. The research provides reference for ensuring high-quality sunflower seeds baking process. [ABSTRACT FROM AUTHOR]

Objective To compare the three different methods for direct transfection of small exogenous nicotinamide adenine dinucleotide phosphate(NADPH) into cells by a non-metabolic pathway. Methods Three different transfection reagents (X-tremeGENETM HP DNA, LipofectamineTM RNAiMAX and LipofectamineTM 2000) were used to find the transfection efficiency of NADPH into human osteosarcoma cell line U2OS and mouse embryonic fibroblast cell line 3T3L1. Their effects on adipocyte differentiation were compared by Oil Red O staining. Results Transfection of NADPH with X-tremeGENE HP DNA transfection reagent effectively increased intracellular NADPH level(P＜0.001). With the increase of NADPH transfection concentration (10 μmol/L NADPH and 10 μL transfection reagent), the level of NADPH in cells increased in a dose-dependent manner. In addition, three transfection reagents were used to transfect NADPH in 3T3L1 preadipocytes. Only cells transfected with NADPH using X-tremeGENE HP DNA transfection reagent contained more lipids than control cells (P＜0.001). Conclusions Transfection of NADPH with X-tremeGENE HP DNA transfection reagent effectively increases the level of NADPH in cells.

In order to improve the drying evenness of the whole layer-type sunflower seed dryer, the optimal design of the dryer was carried out based on ANSYS. The size of hot air inlet section, flow rate and baking medium thickness were taken as design variables, and the reduction of temperature standard deviation of a section of drying layer was taken as the optimization target to analyze the interaction of factors, and the optimal solution was selected by screening method and verified by finite element method. The simulation results show that the flow rate of hot air at the inlet and outlet reaches max.5.933 m/s,and the flow rate tends to be stable after flowing through the first drying layer, so the first layer is the main optimization target. In the interaction of all factors, the sensitivity of inlet flow rate is the largest, and that of thickness is the smallest, and the standard deviation of the cross section temperature of the design points is reduced by 16% compared to that before optimization. This method is different from the heat flow field optimization method of the traditional dryer, and is suitable for the uniformity optimization of the dryer with full section of the drying medium, which provides a reference for the uniformity optimization of the dryer. [ABSTRACT FROM AUTHOR]

In order to solve the problem of atmospheric corrosion of wheel steels during their service，the initial corrosion behaviors of two kinds of automotive wheel steels 590CL and 780CL at 590 MPa and 780 MPa levels in neutral salt spray environment of 5% NaCl solution were studied by neutral salt spray test.The morphology， structure， corrosion rate and electrochemical behavior of corrosion products after salt spray test were characterized by glow spectrometer， metallographic microscope， scanning electron microscope (SEM)， X-ray diffractometer (XRD)and electrochemical measurement.Results showed that after 48 h in the neutral salt spray test， red rust appeared on the surface of the two wheel steels， and the corrosion rates of the two were 590CL＞780CL.The polarization curves and electrochemical impedance spectroscopy results measured in 3.5%NaCl solution were in good agreement with the above results.Besides， the corrosion products of 590CL and 780CL steels were mainly γ-FeO(OH)， and also contained some α-FeO(OH) and Fe3O4.However， the corrosion products basically had no protective effect on the substrate.

Rapid sintering technique has been a hot topic for many years due to it's advantages of saving extensive time and energy. In recent decades, rapid sintering techniques, such as spark plasma sintering, flash sintering, selective laser sintering, induction heating, microwave sintering and fast sintering with conventional sintering element, have been developed greatly and make the rapid sintering of advanced ceramic materials be possible. This article reviews the rapid sintering techniques and the sintering mechanisms during the fabrication of advanced ceramics over the past 20 years, and emphasizes on the effect of pulsed direct current and mechanical pressure on the microstructure, properties and sintering mechanisms during spark plasma sintering. This article also pointed out the development direction of rapid sintering techniques. On the one hand, it would be the further study of sintering mechanisms of rapid sintering techniques and the application of the sintering mechanisms to the industry production of advanced ceramics. One the other hand, to solve the problems of large scale and volume production in the industrialization of rapid sintering would be another development direction. [ABSTRACT FROM AUTHOR]

In order to solve the problem of long-term and multi-point synchronous acquisition and management problems of LAI data in field experiment, a set of full-automatic LAI ad-hoc network monitoring system was designed and implemented. The system supports remote transmission, sampling frequency control and data acquisition, including LAI value, temperature and humidity, node status . Multi-point concurrent communication between the upper and the lower computers has been realized by using the SuperSocker frame communication connection technology. Based on the Pauta criterion, an improved data filtering algorithm was proposed to increase measurement accuracy and reduce data redundancy. Through the JavaScript API provided by Baidu map, the position of the sampling node can be visualized so the experimenter can obtain the sampling coordinates at any time. This system can acquire vegetation parameters automatically and has good user interaction performance, which creates possibility for remote sensing field synchronization experiments. [ABSTRACT FROM AUTHOR]

Based on the double-layer authentication tree and the signature scheme of bilinear algebraic maps, a novel multiple-ten-ant data integrity verification scheme was presented. The double-layer authentication tree structure is introduced to simplify the data integrity verification process and support the dynamic update of data. The regular sampling method is used to improve the signature efficiency of data block. Moreover, the trusted third party (TTP) is introduced to support the batch auditing of multitenancy data and public verification. Experimental results show that the scheme can effectively reduce the TTP verification time and improve the efficiency of integrity verification. [ABSTRACT FROM AUTHOR]

As an important part of Chinese culture, the Bashu culture, precursor of the Sichuan State, originated in the ancient Shu State and went through five dynasties; Cancong, Boguan, Yufu, Duyu and Kaiming. What remains today is the Baodun Culture, the Sanxingdui Culture, the Jinsha Culture and the Shi’erqiao Culture along with the historical and cultural celebrities, the puzzling graphic language, the magnificent myths, the plain but exquisite bronze ware, and the breathtaking music and dance. However, with the changes in contemporary society, how to maintain and promote the spirit of the Bashu Culture has become an urgent issue.

Protein tyrosine phosphatase H-type receptor (PTPRH) gene encodes a gastric cancer associated protein, which exerts its biological function through tyrosine phosphorylation in the post-translational COOH- terminal region. PTPRH is abnormally expressed in a variety of tumors, and its biological function is closely related to the occurrence, development and prognosis of tumors.

Objective: To investigate the indications of the pretemporal transcavernous approach for cavernous sinus tumors resection and design individually tailored surgery according to the extent of tumors and operation requirements., Methods: A retrospective analysis of clinical data, surgical outcomes and complications in a series of 31 cases with cavernous sinus tumor operated via the individually tailored pretemporal transcavernous approach between May 2012 and September 2015 in Department of Neurosurgery, Xiangya Hospital, Central South University. There were 13 male and 18 female patients, aging from 17 to 67 years with a mean of (41±14) years. The patients included 18 cases of shwannomas, 4 cases of meningiomas, 3 cases of cavernous hemangiomas, 2 cases of invasive pituitary adenomas, 1 case of chordoma, 1 case of chondroma, 1 case of recurrent teratoma, 1 case of metastatic nasopharyngeal carcinoma. The first followed-up visit was on the 3(rd) month after surgery, and if tumor progression or recurrence was observed on MRI, the Gamma knife treatment was recommended, the patient was followed up every 6 months, otherwise the patient was followed up again 6 months later, then, every 12 months., Results: Gross total removal of tumors was achieved in 22 cases of 31 patients (71.0%), containing 17 cases of shwannomas, 3 cases of hemangiomas, 1 case of chondroma, 1 case of teratoma; subtotal removal in 6 cases (19.3%), including 3 cases of meningiomas, 1 case of pituitary adenoma, 1 case of chordoma, 1 case of metastatic carcinoma; partial removal in 3 cases (9.7%), comprising 1 case of meningioma, 1 case of recurrent shwannoma, 1 case of recurrent pituitary adenoma. The symptoms of cranial never aggravated in 5 cases, the new postoperative cranial never palsy was observed in 7 cases. There was no surgical mortality, intracranial hematoma, intracranial infection and cerebrospinal fluid leakage cases, ect. Twenty-eight cases were followed up for more than 3 months (3 to 40 months), 1 case of chordoma had tumor progression; the nerve function was restored in 5 cases, among the 12 cases with postoperatively new occurred or deteriorated cranial nerve paralysis., Conclusions: The pretemporal transcavernous approach can be used to resect tumors limited in cavernous sinus or tumors simultaneously involving the cavernous sinus and its vicinity areas, it can be individually tailored based on the extent and exposure of the tumor. This approach can improve the surgical results in terms of high tumor resection rate, less complication, is an ideal approach for cavernous sinus tumor resection.

Objective: To improve the surgical outcome of pituitary adenomas by identifying and preserving the pituitary stalk and the gland during surgery., Methods: From October 2010 to September 2012, the author from the Department of Neurosurgery of Xiangya Hospital, Central South University operated on 51 patients with pituitary adenoma. During the operations, we carefully identified the normal adenohypophysis, pituitary stalk, neurohypophysis and the abnormal tissues either by direct observation or by medical images, aiming to excise the tumor thoroughly, protect the pituitary function and reduce the postoperative complications., Results: Totally 37 patients (72.5%, 37/51) had total resection of the tumor, 12 (23.5%, 12/51) had subtotal tumor resection and the other 2 had major removal. The gland and the pituitary stalk were well identified and reserved. Detection of hormone content proved that the operation had little effect on the free triiodothyronine (FT3) and adrenocorticotropic hormone (ACTH), while for free tetraiodothyronine (FT4) and thyroid stimulating hormone (TSH) and postoperative followup significant alleviation was found. There was no significant fluctuation for the testosterone in the men preoperatively and postoperatively (all the above results were obtained without hormone replacement therapy). The main postoperative complications were as follows: temporary diabetes insipidus in 5 patients (9.8%, 5/51); electrolyte disorder (the appearance of hyponatremia) in 17 (33.3%, 17/51); and cerebrospinal fluid rhinorrhea and postoperative intracranial infection in 1 (2%, 1/51). No one died during the perioperation period., Conclusion: Microscopic transsphenoidal surgery is effective for pituitary adenomas including tumors violating the cavernous sinus. Accurate identification of the pituitary stalk, the gland and the abnormal tissue during the microscopic transsphenoidal operation plays a critical role in preserving the pituitary function and promoting postoperative rehabilitation.