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The industry discards generous organic wastewater in sweet potato starch factory and scrap tea in tea production. A simplified procedure to recover all biochemicals from the wastewater of sweet potato starch factory and use them to make health black tea and theaflavins from scrap green tea was developed. The sweet potato wastewater was sequentially treated by isoelectric precipitation, ultrafiltration and nanofiltration to recover polyphenol oxidase (PPO), β-amylase, and small molecular fractions, respectively. The PPO fraction can effectively transform green tea extracts into black tea with high content of theaflavins through the optimized fed-batch feeding fermentation. The PPO transformed black tea with sporamins can be used to make health black tea, or make theaflavins by fractionation with ethyl acetate. This work provides a resource- and environment-friendly approach for economically utilizing the sweet potato wastewater and the scrap tea, and making biochemical, nutrient and health products.

The first thorough theoretical mechanism analysis of heteronuclear bimetallic cation NiAl+ with cyclohexane has been investigated on singlet and triplet potential energy surfaces (PESs) by using density functional theory. Our calculated results show that NiAl+ can assist in the decomposition of cyclohexane to form benzene through two types of reaction channel: C H bond activation and H2 formation; C C bond activation and HD formation. The most important conclusion is that NiAl+ exhibits high efficiency and also high regioselectivity for C H bond oxidation. However, the high zero-point vibrational energy (ZPVE) value for the cleavage of inert C C bond is also the origin of its failure to form HD. In the process of the first C H and C C bond activations, crossing points (CPs) have been appeared between the two adiabatic surfaces, respectively. The minimum energy crossing points (MECPs) are gotten using the algorithmin Harvey method. Density of states (DOS) is used to obtain a deeper understanding for the roles of the front molecular orbital of the initial complexes. The bonding properties of the special intermediates involved in the process of C C bond activations are discussed by the IR spectrum methods.

Previous studies on the construction of lock-head allow to state that not only provide the means to reduce the stress, but more accurately reflect the actual force of the structure, which are given but there is no effect on the timing of the commissure analysis for the joint project.Based on the design of Xiangjiang River in Changsha integrated hub project, this paper propose the lock structure and layout of the program, in full consideration of the lock complex foundation condition, complex structure, temperature stress and other factors.In this paper, numerical simulation is used to simulate a variety of reasonable construction sequence and construction process, to analysis the characteristics of the stress of the bottom plate of the sluice, the settlement of the foundation and anti-force distribution features. And then discusses the overall stress characteristics and working mechanism of the first structure of the lower gate. On the basis of this, the reasonable construction sequence and structure optimization scheme are put forward.

A core-shell structure RuRh@Pt/C nanoparticles was prepared by using a two-step reduction method under ultrasonic promotion. The catalytic performance was tested in methanol electrooxidation. X-ray diffraction (XRD), scanning electron microscope (SEM) combined with cyclic voltammetry (CV) were used to characterize the obtained catalyst. The results showed that there was no alloy formed between the core RuRh and the shell Pt. The electrocatalytic activity of RuRh@Pt/C varied with the Ru/Rh ratio in the bimetallic core, among which the catalyst with the Ru/Rh ratio 1:2 and the Pt-shell thickness of 1.5 (Ru1Rh2@Pt1.5/C) showed the highest catalytic activity for methanol. With this catalyst, the current density of the oxidation peak for methanol electro-oxidation reached 2.3 times as that of Pt1.5/C while the corresponding peak potential shifted 60 mV negatively in comparing to that of Pt1.5/C. In addition, the catalyst with the core-shell structure of RuRh@Pt/C possessed much higher CO-tolerance for methanol electro-oxidation, indicating its promising application in low temperature fuel cell.

Background:Pneumonia is a common and serious infectious disease that can cause high mortality. The role of lung ultrasound (LUS) in the diagnosis of pneumonia is becoming more and more important.Methods:In the present study, we collected existing evidence regarding the use of LUS to diagnose

Blank image for true orthorectified is the essential components for true orthophoto production, which is based on DSM (Digital Surface Model). It is the first problem to solve after the interior orientation and relative orientation through orthograph rectification reading the original image data. VC++/MFC are used as a development platform to make affine transformation, and then achieve interior orientation. And also linear equation and collinearity equation are used to implement transformation among pixel coordinates and photo coordinates and the ground point coordinates, which is ready for true orthograph rectification assignment of gray using differential correction techniques.