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The demand for proteins with high purity, high activity and high stability is increasing, especially in the biopharmaceutical industry. Traditional industrial protein production technologies include chromatography, which is expensive, and salting out and traditional crystallization methods, which require large amounts of salt and have an adverse effect on the environment. In recent years, a new method—solvent freeze-out (SFO) technology for protein crystallization—has been developed. Compared with traditional methods, SFO requires less salt, and can be carried out at low temperatures, resulting in more stable and active proteins. In addition, SFO can control the nucleation and crystal growth process under different supersaturation levels by setting appropriate operating temperatures, which can ensure industrial application of this technology. This paper reviews important advances in SFO technology for the crystallization of proteins.

The Inconel 600 alloy relies on high temperature strength and aggressive environment resistance for main pipes and heat exchangers for power plant. Through high energy laser beam surface treatment, upgrade oxidation performance and design based accident prevention, the durable Inconel 600 alloy is realized. At the same time, the chemical diffusion and high energy beam welding are used for wearness enhancement and chemical oxidation. It is suggested that, the laser surface treatment and hydrogen effect are accurately selected for abrasive wear resistance and high temperature oxidation, repectively. As a result, the lifespan of Inconel 600 alloy increases, the pitting concentration and cracks formation are prevented effectively.

The Inconel 718 alloy owes high strength and ductility at high temperature due to precipitation strengthening. In order to upgrade productility of Inconel 718 alloy, the Inconel 718 alloy solve hot crackings through Zr additions. The result shows that, the Inconel 718 alloy with Zr addition achieves grain size refinement and homogenization effect. It is suggested that, homogenization process, such as temperature point and time control, realizes low content of Nb segregation which is the key to prevent hot crackings. At the same time, through dendrite space measurement, the grain refinement realize high productivity of forged Inconel 718 alloy, as a another method of soft effect. In conclusion, adding Zr element is one of dominant methods for producing high quality of Inconel 718 alloy.

Protein coding gene annotation errors in prokaryotic genomes are accumulating continually in bioinformatics databases, while the update rate of genome annotation can not keep up with the explosive increasing genome sequences in most cases. Hence it is critical to manually rectify the genome annotation errors. In this paper, a hybrid strategy by combing the gene ab initio predicting programs and the over annotated gene re-annotation programs is proposed for re-annotation of the protein coding genes in prokaryotic genomes. Based on this strategy, the protein coding genes in Geobacter sulfurreducens PCA is comprehensively re-annotated. As a consequence, 16 hypothetical genes are annotated as non-coding sequences and 104 missing genes are retrieved as protein coding genes. Subsequent function analysis and sequences analysis show that the predicting results are much reliable and robust. Further application to other genomes show that this work can provide alternative tools for later post-process of prokaryotic genome annotations.

The segregation behavior through vary cooling speed conditions are achieved through grain redistribution. The result shows that, the severe cooling conditions, such as powerful water and air cooling, perform a great role in fast solidification and texture modification. It is suggested that a fast solidification achieves finer grains at the edges of 60t Q235 steel-casting model. At the same time, the columar grains under extremely cooling circumstances are gradually formed along heat flow redistribution for high density of grain distribution. In summary, the segregation preparation of 60t Q235 steel-casting is completely realized by ProCast® software simulation.

Effects of inoculation quantity, culture temperature and time on glucoamylase activity and the optimum conditions of koji-making of Aspergillus oryzae was studied by using single factor and response surface experiment. The results show that 3 factors can significantly impact on glucoamylase activity of koji. The best process condition of koji-making obtained by using the "Design-Expert" software is: culture temperature 38.70 °C, inoculation quantity 0.85 , and culture time 50.47 h.

‘Hair Like’ crystalline structure grows from most pure tin or zinc finishes. Usually, the diameter of tin whisker is up to 10 mm and the length of tin whisker is typically 1 µm. In detail, the questions for tin whisker formation are classified into 6 categories: 1. Residual stress with in the tin plating; 2. Intermetallic Formation; 3. Externally Applied Compressive Stress; 4. Bending and Stretching; 5. Scratches and Nicks; 6. Coefficient of Thermal Expansion Mismatches. The result shows that, whisker formation could causes electrical short circuit (High current of whisker melting), debris contamination (Sensitive Optical and Micro Electrical Mechanical System) and metal vapor (Vaporize Damage). Thus, it is suggested that environmental tests and standards (Whisker Shape, Temperature, Pressure, Moisture, Thermal Cycling, and Electrical Field) are required for suppressing whisker formation. Nowadays, the new standards committee of Europe Union acts RoHS (Restriction of certain Hazardous Substances) and WEEE...

The nucleation mechanism during the epitaxial graphene films on Si-terminated SiC (0001) surfaces was investigated by atomic force microscopy (AFM) and Raman scattering spectrum. By imaging the change of Si-terminated SiC substrate surfaces, we observed the process of the initial nucleation and the wrinkle formation of graphene. The nucleation of epitaxial graphene phase initiates at 1450°C and the wrinkle formation depends on the thermal decomposition time.

In brick-tea fluorosis affected areas XiLinHot city in Inner Mongolia, herdsmen who like drinking a large amount of brick tea in everyday life and Han habitants rarely drinking brick tea as control group were enrolled, and their hair and urine were sampled. The concentrations of Ca, Mg, K, Al, P, Cu, Zn and Fe in hair and urine were detected using ICP-OES. The RSDs of the method were between 2.32% and 8.03%, and the analytical results of the hair reference samples were consistent with the certified values. The results showed that the contents of Al, Mg and K in hair, and contents of Al and Ca in urine of herdsmen who were accustomed to drinking brick tea were obviously higher than those in control group (P0.05), while the contents of K in urine of herdsmen who were accustomed to drinking brick tea was lower than those in control group (P0.05), and other elements did not have statistic significance (P0.05). Chronically drinking brick tea probably brings metabolic disorder of Ca and Al in human body, and the interaction mechanism of life elements in brick-tea fluorosis should be further studied.

The objective of this study was to detect the fluoride level in the drinking water and the urine of habitants aged 16-55 years living in Inner Mongolia China. Furthermore, fluoride concentration of the brick tea infusion samples which were drunk by Mongolia herdsmen in everyday life living in SumuErga village of Ejin Horo Banner, Inner Mongolia China was also determined. A total of 117 participants (61 female and 56 male) were recruited from two counties for a cross-sectional study on health effects of chronic fluoride exposure from drinking water and drinking brick tea infusion. The fluoride concentration in drinking water, urine and brick tea infusion samples were determined using fluoride ion selective electrode method obtained from the Ministry of Health of the People's Republic of China. The average fluoride concentration in drinking water samples was 0.32 +/- 0.01 mg/L at AretengXire town of Ejin Horo Banner, 0.70 +/- 0.19 mg/L at SumuErga village of Ejin Horo Banner, and 2.68 +/- 1.15 mg/L at ZhalaiNuoer district of Manzhouli city. The average fluoride concentration in brick tea infusion samples which collected from Mongolia herdsmen at SumuErga village of Ejin Horo Banner was 1.81 +/- 1.09 mg/L. The average urinary fluoride concentration at AretengXire town of Ejin Horn Banner was 0.59 +/- 0.48 mg/L, at SumuErga village of Ejin Horo Banner was 1.45 +/- 0.93 mg/L and at ZhalaiNuoer district of Manzhouli city was 3.06 +/- 1.53 mg/L. The higher fluoride levels in the urine of participants may be associated to higher fluoride in drinking water at ZhalaiNuoer of Manzhouli city. However, drinking brick tea infusions with higher fluoride may be the cause of the higher fluoride contents in the Mongolia herdsmen's urine. (C) 2009 Elsevier B.V. All rights reserved.