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The catalysis of ionic liquids (ILs) in the traditional stirred reactor suffers from insufficient mass and heat transfer, which always needs a long reaction time and results in a low reaction rate. In this work, highly efficient synthesis of 1-methoxy-2-propanol via the alcoholysis reaction of propylene oxide (PO) with methanol was proposed and achieved by the combination of micro-tubular circulating reactor with the IL [N4444][Buty] catalyst. Compared with the stirred reactor, the rate of alcoholysis reaction in a micro-tubular circulating reactor was found to be significantly improved. The reaction time was remarkably shortened to 20 min from 180 min as well as the yield of 1-methoxy-2-propanol reached 92%. Moreover, the kinetic study further demonstrated that the main reaction rate to 1-methoxy-2-propanol (K1) was about 20 times larger than the side reaction rate to byproduct 2-methoxy-1-propanol (K2) in the temperature range of 363–383 K. Such combination of micro-tubular circulating reactor with IL catalysts is believed to be a class of effective process intensification technique for highly efficient synthesis of 1-methoxy-2-propanol.

Traditional processes for the synthesis N-OMCs as effective and bifunctional materials for CO2 capture and oxygen reduction reaction (ORR) are unfavorable from the perspective of green chemistry. Herein, we reported the synthesis of N-OMCs through a solvent-free self-assembly route. A N-doped ordered mesoporous polymer (N-OMP) as the carbon precursor was first synthesized from manually mixed terephthalaldehyde, m-aminophenol and Pluronic F127. The precursors were then mechanically mixed with g-C3N4 for carbonization at different temperatures to result in a series of N-OMCs. The resultant N-OMCs were found to have well-developed ordered mesoporosity, and high nitrogen contents of 5.82–6.53 wt%. As a result, the CO2 capacities of N-OMCs can reach as high as 2.46 mmol/g at 0 °C and 0.15 bar, and the adsorption of CO2 by N-OMCs also shows high selectivities towards N2 as well as excellent recycling performance. The ORR activity of N-OMCs is very impressive, with the onset potential of 1.003 V, and half-wave potential of 0.858 V. Overall, the ORR activity of N-OMCs is much better than that of commercial Pt/C catalyst.

A series of new aromatic polyesters containing a (4-phenoxyphenyl)phenylmethene linkage were prepared by phase transfer-catalyzed interfacial polycondensation of 1,1-bis(4-hydroxyphenyl)-1-(4-phenoxyphenyl)-1-phenylmethane with terephthaloyl chloride, isophthaloyl chloride, and so on. The inherent viscosities of the polyesters ranged from 0.62 to 0.90 dL/g, while number-average molecular weights were in the range of 30,500–35,500 g/mol. All the polyarylates were readily soluble in organic solvents such as dichloromethane, chloroform (CDCl3), tetrahydrofuran, meta-cresol, pyridine, N, N-dimethylformamide, N, N-dimethylacetamide, and 1-methyl-2-pyrrolidinone at room temperature, and could be cast into tough, transparent, and flexible films from their CDCl3 solutions. Wide-angle X-ray diffraction measurements revealed the amorphous nature of the polyarylates. These polymers showed glass transition temperatures ( Tgs) between 178°C and 240°C and decomposition temperatures at 10% weight loss ranging from 446°C to 483°C, while the initial degradation temperatures in the range of 410–435°C under nitrogen atmosphere. These new polyarylates exhibited higher Tgs and better solubility than bisphenol A-based analogues.

The exponential stabilization problem of a robot-camera system with unknown camera parameters is investigated. Based on the visual feedback and the state-input transformation, an uncertain chained form model is presented for a type of nonholonomic mobile robots. Then, a new time-varying feedback controller is proposed to stabilize the uncertain system exponentially with the help of the stabilization theorems, state-scaling and switching techniques. The exponential stability of the closed-loop system is rigorously proved. Simulation results are given to demonstrate the effectiveness of the proposed strategies.

It is dangerous for pedestrians to run when the traffic shows a red light, but in some cases the pedestrians are breaking the rules. This system will be a meaningful thing if the jaywalking behaviors of pedestrians in the road crossing through the monitoring cameras could be recognized. Then drivers can be informed of the situations in advance, and they can take some actions to avoid an accident. The characteristic behavior is the non-construction, and furthermore, due to the change of sunlight, temperature, and weather in the outside environment, and the shaking of cameras themselves, the background images will change as time goes by, which will bring special difficulties in recognizing jaywalking behaviors. In this paper, the method of adaptive background model of mixture Gaussian is used to extract the moving objects in the video. On the base of Histograms of Oriented Gradients (HOG), the pedestrians images and car images from MIT Library are used to train our monitoring system by SVM classifier, and identify the pedestrians in the video. Then, the color histogram, position information and the movement of pedestrians are selected to track them. After that we can identify whether the pedestrians are running in the red lights or not, according to the transportation signals and allocated walking areas. The experiments are implemented to show that the proposed method is effective.

MYB-type transcription factor is one of the largest families in plants, which plays important roles in accepting stress signals from environment and regulating the expression of stress-tolerant genes. In this paper, using homologous cloning and RACE technology, a MYB-type transcription factor, designated PeMYB2, was cloned from Phyllostachys edulis. The results of bioinformatics showed that PeMYB2 is a typical R2R3-MYB. It contained two tandem repeats in its N-terminus, and a membrane protein DUF3651 in its C-terminus. In addition, phylogenetic analysis indicated that PeMYB2 shared the highest homology with 85.98% to OsMYB18 protein from Oryza sativa spp. Japonica. In addition, a yeast one-hybrid assay showed that PeMYB2 could activate the expression of downstream genes. After PeMYB2 was transformed into Arabidopsis thaliana, seven PeMYB2 transgenic Arabidopsis lines were obtained. Phenotypic analysis of the transgenic and wild-type Arabidopsis showed that over-expression of PeMYB2 caused delayed flower or dwarfism in transgenic Arabidopsis. Under the abiotic stress conditions, such as salt and cold stresses, the over-expression of PeMYB2 in Arabidopsis had higher survival rate than the wild-type Arabidopsis. Expression analysis of saline stress response marker genes in the transgenic and wild-type plants under the salt stress condition showed that PeMYB2 regulated the expression of NXH1, SOS1, RD29A, and COR15A. As the result, PeMYB2 might play an important role in various responses to abiotic stresses in P. edulis.

Table tennis is a very rapid movement in competitive sports, and its referee needs to make a judgment based on observation and experience within a few seconds, which is a very challenge task. Due to the subjective judgment of the referee’s uncertainty and imprecision, it will lead to some false judgment, resulting in a significant impact on the results of the competition. In the current competitions, the most controversial penalty is the height and angle of the throwing ball’s problem. To solve this controversial problem, this paper designs a complementary video-based recognition of table tennis service umpiring system that can identify and track the location of the table tennis in the video and determine the exact moment when the ball leaves the hand. As a new umpiring system, this paper first introduces into the machine learning methods to identify in table tennis, and discusses a new method of predicting the region of interest to reduce the recognition error rate and improve the recognition efficiency. This system will eventually get through the data of height and angle of the throwing ball, which not only provides a scientific reference for the referees, but also provides a supplementary basis for the athletes to question the referee.

Fingerprint lock cannot work effectively in the case of finger cut or desquamating. Besides, the structure of electronic locks is different from most wooden doors’ and security doors’, and it is also too time-consuming and laborious to change the existing structures. This paper presents a method of opening the door by a mobile robot at home. The robot receives wireless commands and calls the door fixed camera to capture a photo of the visitor. After that, it makes a visual servo based path planning after the verification of the visitor autonomously, then moves from a certain place to the interior door and opens the door. The mobile robot consists of a fixed base 4 degrees of freedom manipulator and a camera. This article focuses on the extraction of work space of the robot, path planning, face recognition, lock positioning, and robotic motion control. Using visual C++ development environment and image processing technology, a controller of the mobile robot to open the door is proposed, the effectiveness of the proposed method is also demonstrated through experiments.

Currently, wearable devices have been paid a great attention in lots of practical fields. This paper discusses the design of two-wheel self-balancing robots based on gesture recognition. The objective is to control the robot’s movement by using gestures. Static gesture recognition without wearing data gloves is exploited to control the motion of the robot. The gesture recognition involves the calculation the distance between the user gesture and template gesture through Hu geometric features. The remote terminal is the Two-wheel Self-balancing Robots. These are unstable and a class of special wheeled mobile robots which are multivariable, nonlinear, strong coupling dynamic system, but it has the characteristics of small, simple, flexible movement. This paper proposes a controller design of Two-wheel Self-balancing Robots, and the simulation results show the effectiveness of the proposed method, which is verified also on the DSP platform at the same time.

The information processed by monocular vision is a target object that projects from 3D to 2D. So restoring the depth information has a significant influence on the prediction of target trajectory and subsequent control decision. This paper proposes an algorithm based on monocular vision, which can be used to calculate 3D velocity of high-speed rotating sphere, this will be applied to vision recognition of table tennis robot, and play an important role in robots’ motion plan and decision control. The experimental results of the proposed algorithm are verified with little error, which proves the feasibility of the proposed method.

Reaction of polystyrene-supported selenium bromide with γ,δ-unsaturated acids and subsequent cleavage from the polymer by treatment with methyl iodide efficiently afforded 5-iodomethyl-dihydrofuran-2-ones in excellent yields. The polymeric reagent can be regenerated and reused as an environmentally friendly reagent.

The stabilization problem of nonholonomic dynamic mobile robots with a fixed (ceiling-mounted) camera is addressed in this paper. First, a camera-object visual servoing kinematic model is introduced by utilizing the pin-hole camera model and a kinematic stabilizing controller is given for the kinematic model. Then, an adaptive sliding mode controller is designed to stabilize uncertain dynamic mobile robot in the presence of parametric uncertainties associated with the camera system. The proposed controller is robust not only to structured uncertainty such as mass variation but also to unstructured one such as disturbances. The stability of the proposed control system and the boundedness of estimated parameters are rigorously proved by Lyapunov method. Simulation results are presented to illustrate the performance of the control law.

Computational chemistry is playing an increasingly important role in drug design and discovery, structural biology, and quantitative structure-activity relationship (QSAR) studies. For QSAR work, selecting an appropriate and accurate method to assign the electrostatic potentials of each atom in a molecule is a critical first step. So far several commonly used methods are available to assign charges. However, no systematic comparison of the effects of electrostatic potentials on QSAR quality has been made. In this study, twelve semi-empirical and empirical charge-assigning methods, AM1, AM1-BCC, CFF, Del-Re, Formal, Gasteiger, Gasteiger-Hückel, Hückel, MMFF, PRODRG, Pullman, and VC2003 charges, have been compared for their performances in CoMFA and CoMSIA modeling using several standard datasets. Some charge assignment models, such as Del-Re, PRODRG, and Pullman, are limited to specific atom and bond types, and, therefore, were excluded from this study. Among the remaining nine methods, the Gasteiger-Hückel charge, though commonly used, performed poorly in prediction accuracy. The AM1-BCC method was better than most charge-assigning methods based on prediction accuracy, though it was not successful in yielding overall higher cross-validation correlation coefficient (q(2)) values than others. The CFF charge model worked the best in prediction accuracy when q(2) was used as the evaluation criterion. The results presented should help the selection of electrostatic potential models in CoMFA and CoMSIA studies.

A facile method for solid-phase organic synthesis of (E)-3-substituted acrylonitriles in good yields using polystyrene-supported α-selenoacetonitrile has been developed. The advantages of this method include straightforward operation, lack of odor, good stability, and high purity of the products.

Reaction of PEG-bound sulfonic acid with thionyl chloride formed the difunctionalised PEG-supported sulfonyl chloride, which was treated with α-hydroxyketones, followed by treatment with 2-aminopyridine in the presence of potassium carbonate efficient to afford imidazo[1,2- a]pyridines in good yields with a facile work-up procedure.

To designed antisense oligodeoxynucleotides (AS-ODNs) to reduce the expression of ATM and to study its effect on the apoptosis of Hep-2 (human epidermoid laryngeal carcinoma) cells treated with radiation in vitro.Experiment was divided into AS-Lipo, Sen-Lipo, Mis-Lipo, Lipo and Hep-2 group. The expression of ATM mRNA in Hep-2 cells was examined by real-time quantitative PCR. About 18 hours after transfection, they were irradiated simultaneously with different doses of X-ray radiation (0, 2, 4, 6, and 8 Gy) respectively. Clonogenic survival assay was carried out to detect the survival ability of Hep-2 cells after irradiation. After exposed to 4 Gy radiation, flow cytometry was carried out to analyze the cell apoptosis.The relative ATM mRNA expression in Hep-2 cells treated with ATM AS-ODNs was decreased to (11.03 +/- 2.51)% which was much lower than that of untreated cells (P0.05). After irradiation, the survival fraction (SF) of cells treated with ATM AS-ODNs was lower than that of other groups at the same dose of radiation. There was statistical significance between the group treated with ATM AS-ODNs and other groups (P0.05). The apoptotic rate for the group irradiated with ATM AS-ODNs was (30.7 +/- 1.31)%, which was significantly higher than that of others (P0.05).AS-ODNs of ATM reduce ATM mRNA expression and enhance Hep-2 cells apoptosis to radiation in vitro.

To constructed the shRNA expressing vectors targeting HBsAg gene and HBeAg gene of HBV, Pgs1, Pgs2, Pgs3 and psiHBV4, psiHBV6 in order to prove their inhibitation on the HBV antigen expression in outlive HepG2. 2. 15 cells.PTZ was used as negative control, both the shRNA expressing vectors targeting HBsAg and HBEAg gene of HBV was together transfected into HepG-2. 2. 15 cells with different combinations, and detected the expression liquid and the cultivated supernatant with MEIA after 24 h.The group transfecting psiHbv4 and PgS2, psiHBV4 and PgS3 could significantly inhibit HBsAg and HBeAg expression compared with control group (P0.05) in the cell disruption liquid and the cultivated supernatant. But the group transfecting psiHBV5 and PgS1, psiHBV6 and PgS3 cannot significantly inhibit HBeAg expression (P0.05) in the cell disruption liquid.The shRNA expressing vectors targeting HBsAg and HBeAg gene of HBV psiHBV4 and PgS2, psiHBV4 and HBeS3 could significantly inhibit the antigen expression of HBV than only one.

To establish a molecular marking method to identify Pinellia ternata and Typhonium flagelliforme.Twenty-two random oligonucleotide primers were used in RAPD analysis on the genomic DNA of two types of Pinellia ternata in Sichuan and two types of Typhonium flagelliforme in Guangxi. The special fragments were sequenced, marked as probes and then conducted Southern blot.A great deal of special bands was found between Pinellia ternata and Typhonium flagelliforme. A Pinellia ternata specific molecule was screened.RAPD analysis and specific DNA probes show potential value in the identification of Pinellia ternata and Typhonium flagelliforme.

AIM: To investigate the sphingosine 1-phosphate (S1P) receptor expression profile in human esophageal cancer cells and the effects of S1P5 on proliferation and mig­ ration of human esophageal cancer cells. METHODS: S1P receptor expression profile in human esophageal squamous cell carcinoma cell line Eca109 was detected by semi­quantitative reverse transcription polymerase chain reaction. Eca109 cells were stably transfected with S1P5­EGFP or control­EGFP constructs. The relation between the responses of cell proliferation and migration to S1P and S1P5 expression was evaluated by 3­(4,5­dimethylthiazol­2­yl)­2,5­diphenyl tetrazolium bromide and migration assay, respectively. RESULTS: Both normal human esophageal mucosal epithelium and Eca109 cells expressed S1P1, S1P2, S1P3 and S1P5, respectively. Esophageal mucosal epithelium expressed S1P5 at a higher level than Eca109 cell line. S1P5 over­expressing Eca109 cells displayed spindle cell morphology with elongated and extended filopodia­like projections. The proliferation response of S1P5­transfected Eca109 cells was lower than that of control vector­ transfected cells with or without S1P stimulation (P < 0.05 or 0.01). S1P significantly inhibited the migration of S1P5 ­ transfected Eca109 cells (P < 0.001). However, without S1P in transwell lower chamber, the number of migrated S1P5­transfected Eca109 cells was greater than that of control vector­transfected Eca109 cells (P < 0.001). CONCLUSION: S1P binding to S1P5 inhibits the proliferation and migration of S1P5­transfected Eca109 cells. Esophageal cancer cells may down­regulate the expression of S1P5 to escape the inhibitory effect.