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To evaluate the thermal storage properties of packer bed under different arrangements o phase change material capsules, three packing models (strip packing model, in-line packing model and disordered packing model) are developed. The index of thermal storage properties for packer bed such as exergy efficiency, energy efficiency, pressure drop, charging time, temperature uniformity, and thermal storage capacity is studied. The results show that the uniformity of the temperature field of the orderly packing model is obviously better than that of the disorderly ones. In addition, the in-line packing model has obvious advantages on the energy efficiency and the thermal storage capacity compared with the strip packing model. The strip packing model has the highest exergy efficiency, but it has a high pressure drop.

The blood-brain barrier(BBB), a protective barrier between brain tissues and brain capillaries, can prevent drugs from entering the brain tissues to exert the effect, which greatly increases the difficulty in treating brain diseases. The drug delivery system across the BBB can allow efficient drug delivery across the BBB by virtue of carriers and formulations, thereby enhancing the therapeutic effect of drugs on brain tissue diseases. Liposomes and micelles have been extensively studied with advances in the targeted therapy across the BBB for the brain due to their unique structures and drug delivery advantages. This study summarized the research status of liposome and micelle drug delivery systems across the BBB based on the literature in recent years and analyzed their application advantages and mechanism in terms of trans-BBB capability, targeting, and safety. Moreover, the problems and possible countermeasures in the research on trans-BBB liposomes and micelles were discussed according to the current clinical translation, which may provide refe-rences and ideas for the development of trans-BBB targeted nano-drugs.

In this work, the condensation heat transfer and pressure drop characteristics of plate heat exchangers were simulated, and the 3-D temperature, pressure, and velocity fields were obtained. From the flow field, we can see that the velocity of vapor is higher than that of condensate. From the pressure field, we can see that the pressure shows a downward trend along the flow direction, and there is, the more pressure drop in the first half of the plate. From the temperature field, we can see that the temperature gradient increases with the increase of velocity and pressure gradient. Meanwhile, the effect of vapor mass-flow, dryness and super-heat on condensation heat transfer coefficients and pressure drops were investigated. The results show that the pressure drop and heat transfer coefficient both increase with the increase of dryness, degree of superheat and mass-flow. In addition, the correlation equations developed to predict the condensation heat transfer and friction factor perfectly agree with the experimental results.

The accurate thermal conductivity of fouling plays a very significant role in designing heat exchanger. In this paper, a novel method of calculating the effective thermal conductivity of particulate fouling is put forward by using IMAGE-PRO-PLUS image processing, the finite element method and ANSYS parametric design language. First of all, according to the analysis on the particulate fouling samples features, the particulate fouling is considered as porous media with fractal characteristics, whose microscopic network model is established using the finite element method, and each unit body material properties are randomly assigned by ANSYS parametric design language. Secondly, effective thermal conductivity of particulate fouling model is calculated by the steady-state plate method. Then, the influence of particulate fouling micro-structure on effective thermal conductivity is explored. Last, it is also show that the calculation resulting of effective thermal conductivity agrees well with available experimental data and empirical correlation. Moreover, it has been shown that effective thermal conductivity of particulate fouling is closely associated with the porosity and pore size. The method can be used to research on the thermal conductivity of fouling, discuss the influence of micro-structure on effective thermal conductivity of fouling, and provide the guidelines for designing of heat exchanger on calculating accurate thermal conductivity of fouling.

To analyze the influence of liquid spraying flow rate on the performance of a falling-film evaporator with R134a, the finite difference model of the horizontal-tube falling-film evaporator is established, and a falling-film air-cooled water chiller with ejector liquid recirculation system (LRS) is presented; then the comparison between numerical simulation and experimental tests are performed. The analysis results show that the experimental and numerical evaporating capacities increase 9.5% and 6.7%, respectively, when the liquid recirculating ratio Rl increases from 1.0 to 1.21; and the deviation between the experimental and numerical capacities of the evaporator is about 3.3%. And that the evaporated liquid flow rate rises quickly at first and then increases slightly as Rl increases. Moreover, the results show that the optimum value of Rl is about 1.2, the corresponding value of integrated falling-film factor φ with about 0.85. This suggests that attempting to eliminate completely the dryout patch outside of tubes is unadvisable.

This paper mainly discusses the relevance of some cooling-water quality parameters and the cooling-water fouling mechanism. By using plate and shell-and-tube heat exchanger experimental systems that are built to simulate the practical operation of heat exchangers, we acquired groups of data of water quality parameters such as Fe3+ and Cl− in the cycle process. Then some interaction analyses were made to study the connection between water quality parameters and fouling deposition, and the results indicate that water quality parameters influence each other in a cycle process and the interconnections of water quality parameters have a direct and obvious impact on cooling-water fouling growth in the early operation stage. Later, fouling growth becomes stable for the reason that each parameter achieves a dynamic balance. Cooling-water fouling growth is a comprehensive result of water quality parameter dynamic changes.

To explore the association of polymorphisms of metabolizing enzyme genes with chronic benzene poisoning (CBP) comprehensively by case-control design.152 CBP patients and 152 workers occupationally exposed to benzene without poisoning manifestations were investigated. 30 single nucleotide polymorphisms (SNPs) in 13 genes such as CYP2E1 were tested by PCR-RFLP, sequencing approaches. Logistic regression model was used to detect main effects and 2-order interaction effects of gene and/or environment. Multifactor dimensionality reduction (MDR) was used to detect high-order gene-gene or gene-environment interactions.Based on logistic regression, the main effects of GSTP1 rs947894, EPHX1 rs1051740, CYP1A1 rs4646903, CYP2D6 rs1065852 and rs1135840 were found to be significant (P0.05) while the confounding factors of sex, cigarette smoking, alcohol consumption and the intensity of benzene exposure were controlled. EPHX1 rs1051740 might be associated with CBP (P = 0.06). There existed 3 types of interactions were as followed: interactions of GSTP1 rs947894 with alcohol consumption, CYP2E1 rs3813867 with EPHX1 rs3738047, EPHX1 rs3738047 with alcohol consumption(P0.05), while the main effects of CYP2E1 rs3813867 and EPHX1 rs3738047 were not significant (P0.05). The other SNPs did not show any significant associations with CBP. According to MDR, a 3-order interaction with the strongest combined effect was found, i.e. the 3-factor combination of CYP1A1 rs4646903, CYP2D6 rs1065852 and CYP2D6 rs1135840.Gene-gene, gene-environment interactions are important mechanism to genetic susceptibility of CBP.

Data entry errors, improper integration, data environment changes, etc., will affect the quality of the data. Among them, the error data is the most serious data quality problems. To clean up the error data, to play the role of information systems and improve the quality of the data, the detection method of error data based on rules is studied, the detection process is analyzed, a common set of detection rules is established, how the SQL statements into the rules is discussed, the detection algorithm is achieved and carried out a series of optimization. This method is easy, its rules are simple, and the efficiency and the false discovery rate are high after optimization. Therefore, this approach may well be a good method of data cleaning.

The main purpose of this investigation was to study the anti-fouling and heat transfer performance of coated surfaces (ECTFE, FEP, PTFE and PFA). In the present investigation, the heat transfer performance of the coated surfaces was compared to base metal surfaces, and crystallization fouling experiments of coated surfaces were carried out under various operating parameters such as solution temperature, solution concentration and hydrodynamics of the system. The characteristic parameters of the coated surface, such as surface roughness, surface contour, contact angle and surface energy were measured and calculated, which were used to analyze the anti-fouling performances of the coated surface. The results show that compared with the base metal surface, Nusselt number of coated surfaces decrease. But coated surfaces have advantage on anti-fouling ability.Copyright © 2010 by ASME

Through load dump tests on Lunnan power plant, it is found that there exist several problems to the dynamic control haracteristic of new generator sets of gas turbine, such as high dynamic response speed of MARS No.2 generator set, large speed overshoot and excessive speed of TITAN-130 generator set. In this paper, the potential reasons for the problems above are analyzed, and some corresponding improving measures are put forward according to the actual condition of electric power pool and generator units

To explore the relationship between polymorphisms of natural resistance-associated macrophage protein 1 (NRAMP1) gene and genetic susceptibility of pulmonary tuberculosis (PTB) in workers exposed to silica dusts.A 1:2 case control study of 61 male workers with PTB (50 silicosis patients and 11 unsilicosis workers) as the case group and 122 male PTB-free workers (100 silicosis patients and 22 unsilicosis workers) as the control group was conducted with the frequency matched for age of +/- 5 years, the job, the silica exposure, and the condition of cigarette smoking and alcohol drinking. The polymerase chain reaction-restrained fragment length polymorphism technique (PCR-RFLP) was used to detect the single nucleotide polymorphisms (SNPs) of NRAMP1 INT4 and D543N.There was a 2.73 times (95% CI: 1.32 approximately 5.64) increased risk of silicosis for individuals with C allele of NRAMP1 INT4 compared with individuals carrying homozygote (G/G), while SNPs of NRAMP1 D543N was not associated with PTB (P0.05).The GC mutation of intron 4 of NRAMP1 gene might be a susceptible factor of silica for the workers exposed to PTB.

To explore the relationship between genetic polymorphisms in apurinic/apyrimidinic endonuclease (APE1) and ADP ribosyltransferase (ADPRT) and individuals' susceptibility to chronic benzene poison ing (BP).A case-control study was conducted. One hundred and fifty-two B P patients and 152 workers occupationally exposed to benzene without poisoning manifestations were investigated. The mismatched bases combined to create restriction site with restrained fragment length polymorphism technique (CRS-RFLP) was used for detecting the single nucleotide polymorphisms (SNPs) at Asp148Glu of APE1 gene and Val762Ala of ADPRT gene.There was no significant difference in the distribution of genotypes of APE1Asp148Glu and ADPRTVal762Ala between the patients and the control groups. Compared with individuals having genotype of APE1Asp148Glu T/T without habit of alcohol consumption, there was a 4.13 times increased risk of BP for the alcohol user with genotype of APE1Asp148Glu T/T (OR = 4.13, 95% CI: 1.07 - 15.85, P = 0.03). The analysis of Logistic regression showed that smoking may play some role in modifying the risk of cironic benzene poisoning (OR = 0.33, 95% CI: 0.14 - 0.75, P = 0.01).The genetic polymorphisms in APE1Asp148Glu, ADPRTVal762Ala are not related to the risk of BP. Potential interaction is found between alcohol consumption and polymorphism of APE1Asp148Glu. Further study is needed to elucidate this interaction.

To explore the relationship between genetic polymorphisms of CYP-1A1 and CYP2D6 and risks of chronic benzene poisoning (BP).A case control study was conducted. 152 BP patients and 152 workers occupationally exposed to benzene without poisoning manifestations were involved. Polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) technology was used for detecting the single nucleotide polymorphisms (SNPs) of MspI in the non-coding region of CYP-1A1 gene and c.188, g.212 position in the first extron of CYP2D6 gene.The individuals with CYP1A1 MspI T/T genotype had a 1.32 times (95% CI: 1.05 approximately 1.65, P = 0.02) increased risk of BP compared with those carrying T/C and C/C genotypes. In no-smoking population, there was a 1.56 times (95% CI: 1.15 approximately 2.12, P = 0.003) increased risk of BP for subjects carrying CYP1A1 MspIT/T genotype compared with those carrying T/C and C/C genotypes. The individuals carrying CYP2D6 c.188 C/C or C/T genotype had a 1.23 times (95% CI: 1.05 approximately 1.42, P = 0.01) increased risk compared with those carrying T/T genotypes. In no-smoking population, there was a 1.23 times (95% CI: 1.04 approximately 1.47, P = 0.01) increased risk of BP for subjects carrying CYP2D6 c.188 C/C or C/T genotypes compared with those carrying T/T genotype. The single nucleotide polymorphism of g.212 position in the first extron of CYP2D6 gene had not been validated.The individuals with CYP2D6 c.188 C/C, CYP2D6 c.188 C/T and CYP1A1 MspIT/T genotypes tend to be more susceptible to benzene toxicity.

To explore the relationship between genetic polymorphisms in hMTH1, hOGG1 and hMYH and risks of chronic benzene poisoning (CBP).A case control study was conducted. One hundred and fifty-two BP patients and 152 workers occupationally exposed to benzene without poisoning manifestations were investigated. The polymerase chain reaction restrained fragment length polymorphism technique (PCR-RFLP) was applied to detect the single nucleotide polymorphisms (SNPs) on c.83 of hMTH1 gene, c.326 of hOGG1 gene and c.335 of hMYH gene.There were 2.51 times (OR(adj) = 2.51, 95% CI: 1.14-5.49, P = 0.02) and 2.49 times (OR(adj) = 2.49, 95% CI: 1.52-4.07, P0.01) risks of BP for individuals carrying genotypes of hMTH1c.83Val/Met + Met/Met or hOGG1c.326Cys/Cys compared with individuals carrying genotypes of hMTH1c.83Val/Val or hOGG1c.326Ser/Cys + Ser/Ser, respectively. Compared with individuals carrying genotypes of hOGG1c.326Cys/Cy and hMYHc.335 is/His at the same time, there was 0.33 times (OR(adj) = 0.33, 95% CI = 0.15-0.72, P = 0.01) risks of BP for these with genotypes of hOGG1c.326Ser/Cys + Ser/Ser and hMYHc.335His/Gln + Gln/Gln simultaneously. In the smoking group, there was 0.15 times (OR(adj) = 0.15, 95% CI: 0.03-0.68, P = 0.01) risks of BP for subjects carrying genotypes of hMYHc.335His/Gln + Gln/Gln compared with these carrying genotypes of hMYHc.335His/His.Polymorphisms of hMTH1 Val83 Met and hOGG1 Ser326Cys may contribute to altered risks of CBP, and potential interaction may exist among polymorphisms of hOGG1 Ser326Cys and hMYH His335Gln.

To explore the association between genetic polymorphisms of XRCC1 and susceptibility to acute childhood leukemia.A case-control study with 63 childhood leukemia patients and 66 control subjects was conducted to investigate the role of three XRCC1 polymorphisms (c. 194, c. 280 and c. 399 ) on susceptibility to childhood leukemia. Genotyping was performed using Polymerase chain reaction-restrained fragment length polymorphism technique (PCR-RFLP) to detect the single nucleotide polymorphisms (SNPs) of XRCC1 gene.There was a 2.235-fold increased risk of childhood leukemia for individuals carrying XRCC1c. 399 Gin allele (95% CI 1.038 - 4.812) compared with subjects carrying Arg/Arg allele, and the OR among boys was 3.110 (95% CI 1.235 - 7.831). No interaction was found between X-ray exposure and XRCC1 polymorphisms using Logistic regression analysis.Polymorphism of XRCC1 gene may contribute to the higher risk of childhood leukemia.

To explore the effects of interaction between environmental exposure factors and genetic polymorphism in toxicant metabolizing enzymes on risk of occupational chronic benzene poisoning.One hundred and fifty-two cases of chronic benzene poisoning were analyzed for the risk by case-only study.The frequency of non-null GSTT1 gene in benzene poisoning workers with moderate benzene exposure level was higher than that in cases with lower benzene exposure (68.63% vs 38.00%, OR(adj) = 4.32, 95% CI 1.75 - 10.66, P = 0.002). The frequency of NQO1 C.609T/T gene in alcohol drinking group was higher than that in non-drinking group (61.11% vs 20.00%, OR(adj) = 8.03, 95% CI 2.28 - 28.25, P = 0.001), moreover, it was higher in workers with smoking and drinking than that in the rest group, and in drinking x exposure level workers than that in non-drinking x exposure level workers (85.71% vs 22.76%, OR(adj) = 18.62, 95% CI 2.01 - 172.72, P = 0.01 and 61.11% vs 20.00%, OR(adj) = 3.18, 95% CI 1.55 - 6.52, P = 0.002 respectively). The frequency of non-null GSTM1 gene was also higher in drinking x exposure level workers than that in non-drinking x exposure level workers (66.67% vs 47.06%, OR(adj) = 1.99, 95% CI 1.05 - 3.76, P = 0.036).There is interaction between the polymorphism of GSTT1 gene and moderate benzene exposure level; non-null GSTM1 gene and drinking x exposure level increase the risk of occupational chronic benzene poisoning; polymorphism of NQO1 gene C.609 also interacts with drinking, while polymorphism of NQO1 gene and drinking x smoking may further increase the risk of occupational chronic benzene poisoning.

To explore the relationship between genetic polymorphisms of microsomal epoxide hydrolase (mEH) and susceptibility of chronic benzene poisoning (BP).A case-control study was conducted. 152 BP patients and 152 workers occupationally exposed to benzene without poisoning manifestations were investigated. Polymerase chain reaction-restrained fragment length polymorphism technique (PCR-RFLP) was applied to detect the single nucleotide polymorphisms (SNPs) on c.113 and c.139 of mEH gene.The risk of BP for individuals carrying mEHc.113 C/C genotype was 0.60 (OR = 0.60, 95% CI: 0.37 - 0.97, P = 0.04) of those carrying T/T and T/C genotypes. In non-smoking population, the risk of BP for subjects carrying mEHc.113 C/C genotype was 0.56 (OR = 0.56, 95% CI: 0.33 - 0.96, P = 0.03) of those carrying T/T and T/C genotypes, and in non-drinking population, the individuals carrying mEHc.113 C/C genotype was 0.51 (OR = 0.51, 95% CI: 0.30 - 0.86, P = 0.01) of those carrying T/T and T/C genotypes.The subjects carrying mEHc.113 C/C genotype and together with non-smoking or non-drinking habit may have lower risk of chronic benaene poisoning.