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The photoinitiated intramolecular hydroetherification of alkenols has been used to form C-O bonds, but the intermolecular hydroetherification of alkenes with alcohols remains an unsolved challenge. We herein report the visible-light-promoted 2-deoxyglycosylation of alcohols with glycals. The glycosylation reaction was completed within 2 min in a high quantum yield (ϕ=28.6). This method was suitable for a wide array of substrates and displayed good reaction yields and excellent stereoselectivity. The value of this protocol was further demonstrated by the iterative synthesis of 2-deoxyglycans with α-2-deoxyglycosidic linkages up to a 20-mer in length and digoxin with β-2-deoxyglycosidic linkages. Mechanistic studies indicated that this reaction involved a glycosyl radical cation intermediate and a photoinitiated chain process.

To analyze the disease types, clinical manifestations, efficacy and outcome of JAK2 V617F and BCR-ABL double-mutant myeloproliferative neoplasms (MPN), and provide a reference for the diagnosis, treatment and prognosis of MPN.The clinical characteristics, diagnosis, therapeutic efficacy and outcome of JAK2 V617F and BCR-ABL double-mutant MPN were analyzed comprehensitively by combining a clinical case diagnosed and treated in our hospital with literature cases from CNKI and PubMed databases.A total of 38 related literatures were retrieved from the two databases by searching "JAK2 V617F" and "BCR-ABL" as key words from 1990 to 2019, and 59 cases were involved. Among all the 60 cases, 41 were males (68.3%) with a median age of 61 (32-77) years old, while 19 were females (31.7%) with a median age of 58 (21-82) years old. The BCR-ABL fusion gene and JAK2 V617F mutation were found simultaneously in 21 cases (35%), 19 cases (31.7%) with JAK2 V617F mutation were found during the treatment of Philadelphia chromosome (Ph)-positive chronic myelogenous leukemia (CML). PhAs cases of BCR-ABL and JAK2 V617F double-mutant MPN are reported, simultaneous detection of JAK2 V617F mutation and BCR-ABL fusion gene in MPN patients is necessary to avoid misdiagnosis and missed diagnosis.JAK2 V617F突变和BCR-ABL融合基因双阳性骨髓增殖性肿瘤临床特征分析.分析JAK2 V617F突变和BCR-ABL融合基因双阳性骨髓增殖性肿瘤（MPN）患者的疾病类型、临床表现、疗效及转归，为此类疾病患者的诊断、治疗、预后判断提供参考。.结合于本院治疗的1例JAK2 V617F和BCR-ABL双阳性MPN患者及文献检索的资料，对JAK2 V617F突变和BCR-ABL融合基因双阳性MPN的临床特征、疗效和转归进行综合分析。.本院收治患者为68岁女性。以"BCR-ABL"和"JAK2 V617F"为关键词在中国知网及PubMed数据库进行计算机文献检索，共检索出1990-2019年38篇相关文献，涉及59例患者。所有患者中，男性41例（68.3%），中位发病年龄为61（32-77）岁，女性19例（31.7%），中位发病年龄为58（21-82）岁。21例初诊时发现有BCR-ABL融合基因和JAK2 V617F突变(35%)，19例在费城染色体（Ph）阳性慢性粒细胞白血病（CML）治疗过程中发现存在JAK2 V617F突变（31.7%），20例存在JAK2 V617F突变的MPN患者在治疗过程中出现PhBCR-ABL及JAK2 V617F双阳性MPN日益多发，有必要对MPN患者同时检测JAK2 V617F突变和BCR-ABL融合基因，以避免误诊漏诊。.

To determine the growth inhibition capability of all-trans retinoic acid (ATRA) with cytokine-induced killer cells (CIKs), we evaluated their effects, alone and in combination, on human lung carcinoma A549 cells. CIKs treated with ATRA significantly inhibited cell growth. Additionally, CIK with ATRA synergistically inhibited migration and invasiveness, colony formation of A549 and NCI-H520 cells. Furthermore, analysis of apoptosis markers Bcl-2, Bax, Survivin and cleaved Caspase-3 showed that Bcl-2 and Survivin mRNA levels significantly decreased, and that Bax mRNA significantly increased, in the CIK + ATRA-treated cells, with corresponding effects on their respective proteins. The involved mechanisms may be associated with upregulated expression of MHC class I-Related Chain (MICA) and interleukin (IL)-2. These results suggest that administration of combined CIK and ATRA is a potentially novel treatment for lung carcinoma.

To meet the requirement of high precision measurement of coordinate measurement machine system, a compact microprobe has been designed for 3D measurement in this paper. Aiming to reduce the influences of signal coupling during the probing process, the probe has been designed by adopting two elastic mechanisms, in which the horizontal and vertical motions of the probe tip can be separated by differential signals of quadrant photodetectors in each elastic mechanism. A connecting rod has been designed to transfer the displacement of the probe tip in vertical direction from lower to upper elastic mechanisms. The sensitivity models in horizontal and vertical directions have been established, and the sensor sensitivity has been verified through experiments. Furthermore, the signal coupling of three axes has been analyzed, and mathematical models have been proposed for decoupling. The probing performance has been verified experimentally.

Charged particles are widely used in the fields of defogging, haze removal and artificial rainfall, and the method of charged particles transport based on the vortex rings can significantly enhance the action region and effect of the charged particles. Transport distance and transport efficiency of charged particles are the crucial evaluation indexes. For the vortex rings produced by a piston/ cylinder installation, the transport distance is closely related to Reynolds number and Formation number (the ratio of piston stroke and piston diameter, dimensionless). Based on the k-omega turbulence model, this paper studies the relationship of transport distance and formation number of vortex rings by using the finite element software COMSOL Multiphysics, and find the optimal formation number, when the transport distance, transport efficiency and maximum transport velocity are simultaneously maximum. The results show that, the optimal formation number is between 0.8 and 1.3, when the Reynolds number at the export of device is about 10,000. In addition, the research results can provide reference for enhancing transport distance of charged particles, especially for the optimization of charged particles transport device based on the vortex rings.

Hybrid electric vehicles present a promising approach to reduce fuel consumption and carbon dioxide emissions. The core technology of hybrid electric vehicles is an energy management strategy to distribute torque between the engine and the electric motor. This study presents an optimized energy management strategy based on real-time control. The operation platform of the control system is based on the dSPACE/simulator, which is a commercial hardware closed-loop system. First, an energy management strategy is built by using an empirical analysis method. To reduce fuel consumption further and to maintain the balance of the battery state of charge, dynamic programming is introduced to achieve the best fuel economy. Optimal gear shifting and engine torque control rules are then extracted into a rule-based control algorithm. Meanwhile, genetic algorithm is introduced to optimize the mode transition rules and the engine torque under parallel mode through an iterative method by defining a cost function over specific driving cycles. Second, a driving cycle recognition algorithm is built to obtain the optimization result over different driving cycles. The real vehicle model is verified by using a hardware-in-the-loop simulator in a virtual forward-facing simulation environment. The energy management strategy uses a code generation technology in the TTC200 controller to achieve vehicle real-time communication. Simulation results demonstrate that the real-time energy management strategy can coordinate the overall hybrid electric powertrain system to optimize fuel economy over different driving cycles and to maintain the battery state of charge.

In this paper, the advantage of hybrid electric vehicle (HEV) equipped with dual clutch transmission (DCT) was presented. Five HEV simulation models equipped with DCT were built on the basis of AVL CRUISE software. According to different power-train configurations, different control strategies were built by MATLAB/SIMULINK. The advantage and disadvantage of each power-train configurations was analyzed through simulation. The results supplied the foundation for the next step vehicle development.

The application prospect of conductive rubber composite is introduced. The mechanism of resistance relaxation of conductive rubber composite was expounded. Several representative mathematical models of the resistance relaxation effect of conductive rubber composite were introduced. The influence of external temperature, heat treatment temperature, the amount of conductive filler, the type and the size of stress, nanomodified materials and dispersing additives on the resistance relaxation effect of the conductive rubber composite were discussed respectively. Finally, a brief description of the application status of conductive rubber composite and its summary and outlook were made.

The conductive silicon rubber samples have been prepared in different filler ingredients, the platform is builded for testing the piezoresistive characteristics of conductive silicon rubber when the material is under water pressure and the test methods are designed, the body piezoresistive properties and surface piezoresistive properties under the water pressure within a certain range are studied respectively. The results show that, the sample of 6% acetylene black/2% nanoSiO2 blends exhibit the best piezoresistive performance when the samples are under water pressure, the piezoresistive properties of the material can be improved with the increase of the thickness of the materials (2mm-4mm), and the conductive silicon rubber used for the pressure-sensitive materials of piezoresistive gauge is feasible.

This paper first describes a variety of heat transfer which exists in cable’s discharge pipe laying process, and analyzes the entire heat transfer process of 10kV three core cable in a two-dimensional interface qualitatively according to the heat transfer ways. Meanwhile, a finite element model of 10kV three-core cable’s discharged pipe-laying is established, and its temperature field equations and boundary condition equations has been discussed. Finally, we get the heat transfer process of the three core cable’s pipe-laying discharged and a finite element model which can be applied to simulated calculation.

A statistics method of the high frequency working area of engine (HFWA) was proposed based on the power required of engine. The power required of engine in different typical driving cycles were statistical analyzed. The weighting function of engine efficiency interval was defined according to the power required, then the degree of engine working efficiency Dm in typical driving cycles was calculated on the assumption of weighting function and efficiency. The more suitable engine of HEV was found by taking Dm as index. Through the simulation analysis and testing, the most economic engine was chosen from the optional engines.

Compressive sensing (CS) theory asserts that one can recover original signals from far fewer random samples under the condition of being sparse. CS theory is applied to high resolution imaging of vehicle-mounted stepped-frequency forward-looking ground-penetrating radar. This paper explores an approach of obtaining discrete scattering structure of the metal mine based on CS imaging and extracting geometry parameters to discriminate targets. Real data of vehicle-mounted stepped-frequency forward-looking ground-penetrating radar is processed. High resolution images of the metal mine with double-scattering structure are obtained. The feasibility of the method is tested through these images.

As we know that ceria (CeO2), alumina (Al2O3), aluminum (Al) and iron oxide (Fe2O3) can improve the anti-aging properties of the rubber, mixed these materials with carbon black and filling conductive silicone rubber, some samples have been prepared. Have described the anti-aging method of the silicone rubber and discussed the test method of the changes in properties after aging. Have tested the changes of mechanical properties and electrical conductivity before and after the air aging test of the conductive silicone rubber which with or without addition of modified material. Have discussed the reasons why modified materials can improve the anti-aging performance of the conductive silicon rubber. The results show that with the addition of these types of nanomaterials the stability of mechanical and electrical properties of the conductive silicone rubber can be improved before or after aging treatment.

Magnetic suspension type belt conveyor used magnetic machinery technology design can solve the belt conveyor of roller support parts number, large energy consumption and high maintenance cost, limited tape speed, large noise and other issues. Magnetic belt conveyor design is the key to stability analysis of the operation of conveyor belt. Papers from a mechanical point of view to study the structural stability calculation. The results show that small interfering in the external magnetic conveyor belt, the permanent support system can be adjusted to spontaneously stable equilibrium state.

Planetary power-split hybrid vehicle is a very common structure of hybrid electric vehicle (HEV), which achieves speed and torque double decoupled between engine and wheels. Engine always working on optimal curve is an important reason for low fuel-efficient. Engine speed is controlled by PID, and the optimal loading rate of engine is solved from engine characteristic curves; finally realization of engine working on optimal curve. Offline simulation is used for this algorithm, and comparing with many experimental results demonstrates engine works on operating point; fuel consumption is close to the official fuel consumption of Prius.

EVT transmission in Planetary Gear Hybrid Electric Vehicles makes it available that the engine works on the optimal curves; yet because of the speed limitation of motor MG1, the maximum output power of the engine is a function of vehicle speed. The maximum traction and regenerative braking power is also a function of vehicle speed. Based on this, the vehicle drive modes consist of EV mode, economy mode and power mode, and braking modes include the regenerative braking mode and electromechanical braking mode.

THS II[1-3] is one of the most popular HEV configurations which has three power sources: an engine, an electric motor and a generator. When the engine is started, the dynamic response of engine will cause the vehicle to be power failure or great fluctuation. Therefore, in order to ensure good effect of vehicle dynamic coordination, it is necessary to use the electric motor's torque compensation principle to achieve dynamic coordination control of power sources, during the period of mode switch.

Compressive Sensing (CS) is a recently developed technique, which can reconstruct the sparse signal with an overwhelming probability, even though the signal is sampled at highly sub-Nyquist rate. Based on the observation that the electromagnetic scattering structure (ESS) of a metal landmine is composed of two scattering centers, whose geometrical parameters are tightly related to its physical dimensions, a new physics-based landmine discrimination approach is proposed in this paper. Firstly, the approach uses the Multi-Measurement Iterative Pixel Discrimination method to reconstruct the landmine's ESS in noisy environments. Secondly, the geometrical parameters of the landmine's ESS are extracted from the sparse image. Thirdly, landmine discrimination is conducted according to the measured geometrical features and apriori knowledge. Finally, the fleld experimental results demonstrate the efiectiveness of the proposed approach.

As human overexploitation of non-renewable fossil fuels such as mining resources, the global environment has been severely polluted and damaged, which also poses a threat to human's health. So it is full of demands for renewable and clean energy sources. At present R & D of new energy is also increasing emphasised around the world. HDR as a renewable clean geothermal resources, with large reserves, widely distributed, heat, environmentally friendly development, through the heat exchange technology for power generation, which has a strong potential value.To actively develop new energy and promote the application of HDR power generation technology,we start from the basic characteristics of the HDR, and explore the basic principles of HDR power generation, the key technologies and the development of economic conditions. Meanwhile combined with the geographical characteristics of the environment in China, from the perspective of integration of subject resources,finally we constructively put forward a three-stage strategy for HDR power generation development plan.

Temperature is an important parameter for the characterization of the transformer and the motor running. Winding temperature test according to the actual operation of the traction transformer and motor temperature protection device requirements, in-depth study, temperature test of the traction transformer based on virtual instrument and traction motor winding resistance method, the method using LabVIEW to develop test software, respectively, for data acquisition, data playback, data analysis and processing, data file management functions, and temperature test equipment, not only real-time test system, but also post-processing the data after the test, in order to analysis of the factors that affect the temperature of the windings. Validity of the method is proved by experiments.

At present, the security has become an important issue in the field of cloud computing. The importance and urgency of the problem cannot be ignored. The popularization and application of cloud computing is a great challenge and opportunity in the field of information security in recent years. It can be seen that cloud computing security is changing to a hot spot for technology and academic research in cloud computing. This paper is aim to solve the problem of Cloud Security. According to the unique properties of cloud computing security, it proposes a secure management scheme in cloud computing. This scheme is used to detect the hacker attacks, illegal operation, potential threats and other security events in time based on big data. There are three main sections in the scheme: vulnerability scan, system log collection, correlation analysis. They are simply introduced and analyzed in this paper. Vulnerability scan: regular using of Nikto, Sandcat or other security tools for the cloud system to carry out the vulnerability scanning, regular network security self-testing, and building an extremely detailed scan report. System log collection: Using of Splunk, Nagios or other tools to collect the system log, also building a detailed log report. Correlation analysis: through the correlation analysis or canonical correlation analysis is used on the system log reports and vulnerability scanning reports, the attacker's attack will be found and the system will be issued a warning in time. At last, the scheme was built in the company's test environment, then the test environment was attacked by penetration test which is to simulate the act of hacking, the feasibility and function of it are verified by the testing.

The maternal genetic effects on estimating genetic parameters for growth traits and wool traits of Qinghai fine-wool sheep were investigated.The genetic parameters for production traits of Qinghai fine-wool sheep were estimated by average information restricted maximum likelihood (AIREML) with different animal models, and the differences between different animal models were tested by likelihood ratio test. Fixed effects, direct genetic effects, and residual effects were included all models; and random effects were individual permanence environmental effects, maternal genetic effects, and maternal permanence environmental effects. The six models differ in the way of considering random effects: in model 1 individual permanence environmental effects, maternal genetic effects, and maternal permanence environmental effects were not contained; in model 2 maternal permanence environmental effects were included; in model 3 maternal genetic effects were included; in model 4 both maternal genetic effects and maternal permanence environmental effects were include; in model 5 both individual permanence environmental effects and maternal genetic effects were contained;in model 6 all random effects were contained. The direct heritabilities were 0.1896~0.3781, 0.2537~0.2890, 0.2244~0.3225, 0.2205~0.3983, 0.1218~0.1490, 0.0983~0.4802, and 0.1170~0.1311 for birth weight, weaning weight, yearling weight, hogget weight,greasy fleece weight, fiber diameter, and staple length,respectively. Compared with model 1, model 3 was-significant(P 0.05)for Yearling weight, Hogget weight; and paralleled with model 6, both model 4 and model 5 were significant(P 0.05) for greasy fleece weight by likelihood ratio test.The maternal effects were important determinants of estimated the genetic parameters for birth weight, weaning weigh, fiber diameter, and staple length, but were not significant for yearling weight, and hogget weight, and was slightly significant for greasy fleece weight.

Parallel-series is a kind of hybrid configuration which is used in excavator. This configuration can give full contribution to the energy saving potential of hybrid excavator. In the paper, based on the cycle power of excavator, the hybrid power-train’s parameters are matched. Then we analysis the matching results on the software simulation model we have built. The simulation results show that using this method the system can meet the power demand of excavator, and the efficiency of the excavator was improved.

A control strategy which based on minimum instantaneous equivalent fuel consumption was proposed in this paper. The important parameters that affected the calculation of instantaneous fuel consumption were analyzed. The important parameters include battery equivalent fuel consumption, penalty function to maintain the battery SOC and the revise of the regenerative braking energy. More precise expression of minimum instantaneous fuel consumption was deduced. Under the simulation platform of ADVISOR software, orthogonal optimization of parameters was performed and the range of important parameters in the optimization of expression was determined.