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A novel galactoside derivative (1) incorporatingp-nitroaniline (p-NA) as chromophore has been synthesized and used as a cascaded chromogenic enzyme substrate for the detection of β-D-galactosidase, which was characterized using UV,1H NMR,13C NMR and MS spectra. A plausible mechanism for the release ofp-NPA from the enzyme substrate 1 was proposed.

The method of predication is the key for evaluating lifetime remaining of existing bridge in bridge assessment. Improved Gray Model,which can supplement and make full use of new information in time,on the basis of Gray Theory is tried to be used here,and compared with traditional model by analysizing an engineering case.The results show that the improved model can not only improve the precision of prediction,but also comply with the nature of dynamic property of bridge lifetime remaining,i.e.,as the latest inspection information updates the predication value.

The SiO2/NaGdF4:Eu3+ core/shell composite was prepared by a template-mediated method, making monodispersed SiO2 as core and NaGdF4:Eu colloids as shell, the morphology and the core-shell structure of the resulting particles were analyzed by SEM,X-ray diffraction, and the photo-luminescence and magnetic properties of the microspheres were investigated too. The results shows the composite have great potential to be used as homogeneous magnetic/optical bifunctional material.

In this paper, we fabricated the 4-aminobenzenethiol modified gold nanoparticles onto polymer spheres as SERS substrate to selectively detect 2,4,6-trinitrotoluene (TNT) explosives. The gold nanoseeds were fixed on polymer surface by reduction of HAuCl4·3H2O with sodium citrate. About 60~100nm nanoparticles were formed from the previous seeds and self-assembled by 4-aminobenzenethiol. The functionalized gold nanopartilces aggregation coated on large polymer sphere surface not only absorbed more TNT molecules via conjugation system, but also generated numerous "hot spots". It was demonstrated that this substrate displayed high SERS activity for TNT detection. It could also be anticipated that the aforementioned material would be used for fast and sensitive SERS detection of TNT in real-world situation. Keywords: gold nanopartilces, SERS, TNT, functionalization

1,2,3-Triazole linked carbohydrate and podophyllotoxin were synthesized in high yield and selectivity. The CuI-catalyzed Huisgen’s [2+3] cycloaddition of azides and alkynes was proved to be powerful tool for constructing podophyllotoxin derivatives.

Three prediction models for concrete carbonation were investigated based on 79 groups accelerated carbonation data collected from the references. Model comparison and experimental verification demonstrate that the empirical models are simple and convenient for engineers, but it is often limited to the set of conditions under which they are developed. However, the theoretical model derivated from the carbonation mechanism and the mass conservation of carbonatable constituents is of good accuracy and applicability to real life scenarios.

P1,P2-Diaciclovir-5'-diphosphate has been synthesized efficiently from aciclovir 5'-H-phosphonate monoester via a one-pot reaction. This method features easily accessibleH-phosphonate starting material, short reaction time, and good isolated yield.

A new unsymmetrical photochromic diarylethene 1o, which is named 1-(2- methoxyphenyl)-2-[2-methyl-5-(1,3-dioxolane)-3-thienyl]perfluorocyclopentene, was synthesized. Its photochromic and simulated molecule structure were also investigated in detail. This diarylethene underwent reversible photochromism, changing between colorless and blue in hexane solution upon appropriate irradiation with UV/vis light. The kinetic experiments illustrated that the cyclization/cycloreversion process of this compound was determined to be the zeroth/first reaction. In addition, this compound can be used as optical recording materials.

A general synthesis of nucleoside 5'-phosphoromorpholidates from carboxybenzyl-protected nucleosides has been developed. Phosphitylation, acid-catalyzed hydrolysis, and oxidative coupling generated the phosphomorpholidate products in high yields.

Fungus has been valued as one of edible and medicinal resources, and bioactive substances have been identified in many fungus species. In all of them, polysaccharides are the most famous and potent fungus-derived substances with antioxidant, antitumor, immunoregulation and so on. Although the isolation process and bioactive activity of fungal mycelium polysaccharides have been investigated in the past decade, the new bioactive activity and the mechanism of fungal mycelium polysaccharides are not systematic studied. These studies are still in progress and the role of polysaccharides as bioactive activity is especially under intense debate. The purpose of the present review is to summarize the available information of isolation process and bioactive activity, and to reflect the current status of these research areas with a view for future direction.

This paper first introduces the test profile of Reliability Enhancement Testing(RET) then completed in the past three years, a large number of the implementation results of the RET test were statistically analyzed, given the distribution of the design defect, the last two design defects excitation and elimination process were be detailed explanation, and demonstrated it is exceptionally effective that the RET test inspire and eliminate electronic product design defects.

Based on the thermal calculation, the paper makes a contrastive analysis on the parameters of flue gas, and convection heat properties of the coal-fired boiler under atmospheric air combustion, atmospheric oxy-fuel combustion and pressurized (6MPa) oxy-fuel combustion conditions. It takes a 300MW pressurized(6MPa) oxy-fuel combustion boiler as research object, the result indicates that: compared to the coal-fired boiler atmospheric air combustion, the flue gas volume flow in the pressurized oxy-fuel combustion has a decrease of 98.79%; convective heat output has a decrease of 24.69% with the same difference in temperature. In the pressurized oxy-fuel combustion, both the flue gas convective heat transfer coefficient and the pressure drop are greater than the atmospheric oxy-fuel combustion, flue cross-sectional area is smaller than conventional boiler, and heating surface area is less than atmospheric oxy-fuel combustion. With a method named dynamic minimization of costs the best flue gas velocity in this paper is 1.07m/s

This study was conducted to investigate the efficiency of TiO2 photocatalytic nanomaterial as a novel environment-friendly disinfectant to control plant fungal diseases (Sphaerothecaf uliginea) by its photochemical sterilization ability in cucumber plants. Anatase nano-TiO2 sol, a neutral, viscous aqueous colloid of 1.4% TiO2, was synthesized by sol-gel method. Control efficiencies of nano-TiO2 sol in preventing from powdery mildew were measured by field experimental method with cucumber seedling naturally infected Sphaerothecaf uliginea. Results showed that spraying certain content of nano-TiO2 sol could form continuous and stable antibacterial films on blade surfaces which could not only significantly reduce lesion areas, disease incidences and disease indexes of powdery mildew but also make the leaves turn much greener. It was initially confirmed that nano-TiO2 sol could effectively delay and inhibit the development and pervasion of cucumber powdery mildew. These results indicate that nano-TiO2 sol can be developed as environment-friendly fungicide in preventing from plant disease developments.

Biological multilayer films of redox polymer and horseradish peroxidase (HRP) were successfully assembled on a screen-printed carbon electrode using layer-by-layer (LBL) assembled method based on the electrostatic interaction. The screen-printed carbon electrode surface was modified by the positively charged redox polymer, and the negatively charged HRP by LBL method.

The canna amylose (CAM) was separated from canna starch grown in China and purified both using the method of n-butanol recrystallization. The purity, morphology, spectral properties and molecular weight of CAM were characterized by ultraviolet and visible spectrophotometer (UV/Vis), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscope (FT-IR) and Ubbelohde viscometer. Maximum absorption wavelength of the purified CAM (635－638 nm) and it’s blue values (BV) (1.167 ± 0.209) prove that the purification of the CAM by n-butanol recrystallization was successfully carried out. The SEM results show that CAM granule surface become rougher and the CAM granule size become smaller than that of canna starch. The XRD results suggest that most of CAM granule is amorphous. And the FT-IR results show that the basic chemical groups of canna starch are also presented in CAM. However, the amorphous area of CAM is increased. The intrinsic viscosity and viscosity-average molecular weight of CAM is 78.5 mL/g and 1.65×105, respectively.

In the current market demand of rapid response manufacturing, the product variant design technology is one of the key technologies. Product variant design principles and methods are first described. Then, product dimension parameter is analyzed and product dimension parameter transferring structure is studied. Applying tree theory to product variant design, a dimension relation driving-tree of components and parts is constructed and the significance of driving-tree statistics and a dimension parameters transfer method are presented. The methods and processes which are applied to variant design and the sorting algorithm of relations are described in detail. A parameterized variant design module integrated with SolidWorks was developed with VC + +. All the above mentioned methods and processes are verified by taking a joint coupling product as an example.

Properties of plain concrete and polyacrylonitrile fiber concrete, including fatigue resistance performance，flexural toughness and impact resistance performance were respectively studied．Improved effect on airport pavement classification number(PCN)by the addition of polyacrylonitrile fiber in concrete was then analyzed．Experiment results showed that all property indexes of concrete increased greatly，and pavement classification number also was enhanced by the percentage of 8.4．In this way，load-carrying capacity of airport pavement was enhanced greatly．

Aiming at the problem of low recognition rate and easy affected by environment during the process of robot target recognition in complex environments, the target recognition method combining support vector machine (SVM) with D-S evidence theory was proposed. Taking citrus recognition as an example, SVM was used by the method to local classification according to citrus color and geometry feature information respectively, and the results of SVM were transformed to probability outputs through Platt model, and treated them as the basic probability assignment (BPA) of D-S evidence theory to reason and fuse local recognition results, and then realized the combination of SVM and D-S evidence theory in citrus recognition, finally improved the recognition rate. The experimental results showed that: the recognition rate of the method combining SVM with D-S evidence theory and integrating color features and geometry features was higher than SVM method with only color or geometry features.

Rigid tapping of NC Tapping center is an electromechanical control system which is strongly nonlinear, uncertain and difficult to precise modeling. It is unavoidable to be affected by some nonlinear and uncertain factors such as friction and mechanical resonance. The traditional control method could not fundamentally solve the contradiction between rapid stability and high stable precision of the system response. As an intelligent control method, fuzzy control is actually a kind of PID regulator, and it exists a strong complementary to PID control in the system dynamic and static characteristics. This paper introduced fuzzy adaptive PID control applied to NC rigid tapping in engineering practice, the control method need not to build the controlled object, using mathematical model of fuzzy reasoning method for the online PID parameters auto-tuning, it met the system well for the rapidity and smoothness of comprehensive index requirement and technical realizability, finally through test platform test, numerical control machine tool actual tapping was validated.

Artificial neural network (ANN) and evolutionary algorithm (EA) are both biology-based models of information processing. The basic theories of ANN and EA are described. Then the mechanisms of using EA for ANN’s optimization are explained and the research states are summarized. The existing problems and future directions are demonstrated finally.

The interesting finding is reported that unusual calcium carbonate (CaCO3) microspherules had been synthesized by simply mixing calcium chloride and ammonium bicarbonate with the assistance of dihexadecyl phosphate (DHP, an anionic lipid). The experimental results indicate that as-prepared CaCO3microspherules with complex surface texture are predominantly vaterite with high stability. DHP plays a critical role in the formation of the well-defined CaCO3microspherules.

There are most important features hiding in the higher-order statistics information of the images. They are extracted by classical fast-fixed independent component analysis (FastICA algorithm) which requires a large amount of calculation and it is sensitive on the selection of initial point. To overcome the two shortcomings, an improved FastICA algorithm is proposed and mathematical models are constructed. And they are applied to obtain the basic vectors from the images. Finally, take litchi fruit image in natural environment as an instance and experiment with Matlab software. The results show that there are less computation and stronger stability of the improved FashICA algorithm used to extract image features.

A novel porous CaO microsphere catalyst was synthesized by calcining spherical CaCO3 precursor which was prepared easily by mixing CaCl2 with Na2CO3. After characterized by scanning electron microscope and X-ray diffraction analysis, the synthesized CaO was studied on Studies on the catalyzing transesterification of soybean oil with methanol for biodiesel. The effects of calcining temperature, reaction time and temperature, amounts of catalyst and methanol on the catalytic activity of CaO microsphere had been evaluated by catalyzing transesterification of soybean oil with methanol for biodiesel. It expressed excellent catalytic activity with a transesterification yield of more than 98% at 65 °C in one hour with 3 wt% of CaO microsphere calcined at 800 °C.

In this paper, calcined river-snail shell was used as a novel solid base catalyst in the transesterification of soybean oil with methanol for biodiesel production. The calcined river-snail shell was characterized using field emission scanning electron microscope and X-ray diffraction. Effects of transesterification process variables were investigated. The results indicated that river-snail shell calcined at 800 °C catalyzed the transesterification of soybean oil for biodiesel with a yield over 98 % under the conditions including catalyst of 3.0% (w/w), a molar ratio of methanol/oil of 9:1, reaction time of 3 h, and reaction temperature of 65 °C. As a low-cost green catalyst, calcined river-snail shell could not only minimize the environmental wastes resulted from the solid shell, but also reduce the production costs of biodiesel.

The polymer melts viscous dissipation effects of micro scale dimensions are different from that of macro-scale dimensions. In this paper, the temperature rises due to viscous dissipation were investigated when amorphous polymer material, PMMA, flows through several micro-channels with the diameters of 350μm, 500μm and different aspect ratios. The results indicate that, temperature rises reduce with the increase of inlet temperature of melt and increase with increasing channel’s diameter and aspect ratio at the same shear rate. The outlet temperature rises due to viscous dissipation in all micro channels increase with the increase of shear rate. In addition, the outlet temperature rise grows faster with the decrease of micro-channel’s diameter. Therefore, viscous dissipation effect is significant and should not be neglected in micro channel.

According to different environment and working requirement, the manipulators with diverse shapes and functions are required. In this paper, a virtual design and simulation system for manipulators of multi-degree of freedom (DOF) was put forward. Knowledge classification and modeling were carried out for the manipulator’s mechanism and motion behaviors. The software architecture framework and platform of the hardware and software were described. The overall program approach and its realization of the system were introduced. Based on the VC++ 6.0 development platform, the manipulator’s design and simulation system was developed and tested by examples. The results show that it provides a theoretical method and a tool for the virtual design and virtual manufacturing of multi-DOF manipulators in complex environment, which elevates the speed and lowers the cost of research and development.

In order to reduce the research and experimental cost of hand-picking machine, to make the design of manipulator more reasonable, and to provide more optimized program for the design, an agricultural picking manipulator simulation system based on intelligent design was designed. Firstly ,based on the research needs, to simplify the real picking manipulator under the premise of that the simulation accuracy reach the requirement, the model of picking manipulator had been simplified. Secondly, the finished model was put into EON Studio to build the virtual procedure, and movement properties were added to the manipulator to realize the function of motion simulation. Thirdly, the picking manipulator mathematics motion model of 4 freedoms was established, and the inverse kinematics of the picking manipulator was analyzed by MATLAB analysis tools, and the reverse solution program was written. Finally, Microsoft Visual C++ was used to complete the design of simulation platform, in order to realize the calling of various functions of the manipulator.