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To prepare a gold plating layer with good bonding strength and weldability on the surface of Al-SiC composite materials，experiments exploring pre-treatment and surface metallization processes of materials were conducted.It was determined that using sensitization and activation directly on a clean，activated surface of substrate could achieve uniformity of heteroatomic autocatalytic center atoms on the surface of Al-SiC materials.Subsequent chemical nickel deposition was performed using a nickel sulfate system，followed by electroplating gold to form a uniform and dense gold plating layer on the substrate surface.The coating’s cross-section and surface morphology were analyzed using scanning electron microscopy (SEM).Results showed that the surface of the gold layer was uniformly colored，with uniform，continuous thickness and good bonding strength，demonstrating the feasibility and rationality of this process method.This study had significant implications for guiding subsequent gold plating production on Al-SiC materials.

The quality and physiological changes of ‘Luli’ and ‘Gala’ apples during low-temperature storage were explored to provide a theoretical basis for the storage and preservation of new mid-early ripening apple varieties. The results showed that the hardness, soluble solids content and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity of ‘Gala’ and ‘Luli’ apples showed a downward trend during cold storage and the shelf life period. After 90 days of storage, the hardness of ‘Gala’ apples decreased by 56.3%, while that of ‘Luli’ apples decreased only by 30.7%. Compared with ‘Gala’ apples, ‘Luli’ apples had lower polyphenol oxidase and lipoxygenase activities and higher contents of total phenols, flavonoids and chlorogenic acid during storage. During low temperature storage, the contents of individual phenolics in ‘Luli’ apples decreased, and the contents of chlorogenic acid, epicatechin, hypericin, and ferulic acid decreased most in the first 15 days, but did not significantly change during the shelf life period. The contents of catechins, p-coumaric acid, rutin, and caffeic acid in ‘Gala’ apples increased slightly after 15 days of low temperature storage and then decreased, but decreased gradually during the shelf life period. The contents of all phenolics decreased during the shelf life period. The major aroma components in ‘Gala’ and ‘Luli’ apples were aldehydes, alcohols and esters, among which 3-methyl-2-buten-1-ol, isoamyl benzoate, nonanal, 2-amino-6-methylbenzoic acid, 1-methyldibenzofuran and diisobutyl phthalate were only detected in ‘Luli’ apples. During low-temperature storage, the relative contents of aldehydes in both varieties decreased, while the relative contents of alcohols and esters showed an increasing trend. The relative content of alcohols in ‘Luli’ apples decreased during the shelf life period, while the opposite trend was observed for ‘Gala’ apples. In conclusion, ‘Luli’ apples exhibited higher fruit hardness, antioxidant capacity and phenol content during low-temperature storage and the shelf life period, and the overall storage quality was better than that of ‘Gala’ apples.

Mid-early maturing apples can enrich the fruit market and constitute an important part of the apple industry. It is of great significance to study the quality and storage characteristics of mid-early maturing apples. In this study, ‘Luli’ and ‘Luyan’ apples as well as their parental variety Gala (as a control) were investigated for differences in their storage quality and phenolic composition. The results showed that ‘Luli’ apples had higher soluble solid content (SSC) and skin a* value and better appearance quality compared with ‘Gala’ apples, being suitable for fresh consumption. However, ‘Luyan’ apples possessed high total acid content and low solid/acid ratio, produced a largest amount of ethylene during storage, and had poor storability. Compared with ‘Gala’ and ‘Luyan’ apples, ‘Luli’ apples had higher contents of total phenolics and flavonoids and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity, indicating stronger antioxidant capacity. The main phenolics in apples varied depending on the variety, maturity and fruit part. Chlorogenic acid was the most abundant phenolic compound in ‘Luli’ and ‘Gala’ apples, while epicatechin was the most abundant phenolic compound in ‘Luyan’ apples. The content of phenols in the peel was higher than that in the pulp. Correlation analysis and principal component analysis showed that fruit firmness had a significant negative correlation with a* value (P < 0.001), and SSC had a significant positive correlation with the contents of total phenolics, total flavonoids, chlorogenic acid and DPPH radical scavenging capacity (P < 0.001). Principal component 1 (PC1) is mainly determined by the content of total phenolics, total flavonoids, chlorogenic acid, and epicatechin. Mature ‘Luli’ and ‘Gala’ apples are relatively similar in PC1. This study provides a reference for the preservation and processing of mid-early maturing apples.

The AlCrSiN/Mo self-lubricating coating was prepared by hybrid technology of high power impulse magnetron sputtering and pulsed DC magnetron sputtering, and the structure and properties were modified by vacuum annealing. The influence of vacuum annealing temperature on composition, microstructure, mechanical and tribological properties of AlCrSiN/Mo coatings was systematically investigated by scanning electron microscope, X-ray diffractometer, electron probe analyzer, nano-indentation tester, scratch tester and friction and wear tester. The results show that all the AlCrSiN/Mo coatings possess the nanocomposite structure, namely the nc-(Al,Cr,Mo)N is surrounded by a-Si3N4 amorphous phase. After vacuum annealing, the particle size on the coating surface is increased significantly, whereas the nanohardness and critical load of the coatings are decreased correspondingly, and the wear resistance and antifriction performance are improved significantly. After being annealed at a temperature of 700 ℃, the coating presents the optimum properties with a nanohardness of 18.3 GPa, a friction coefficient of 0.51 and a wear rate of 3.4×10-4 μm3·(N·μm)-1. In this case, the characteristic values of H/E and H3/E*2 keep the highest.

[Objectives] With the rapid development of space technology, launching aircraft at sea has gradually become a future development trend. Aircraft flying in the atmosphere will sometimes encounter lightning strikes, which can cause damage to airborne equipment.[Methods] In response to this issue, two aircraft models (one with a gap and one with no gap) are built. Based on the CST transmission line matrix method, the induced electric and magnetic fields, surface current and induced current distribution of the cables of the two aircraft models are studied. At the same time, the changes in induced current in cables of different lengths are studied.[Results] For the same aircraft model, the surface electric and magnetic fields and internal electric and magnetic fields at the same axial position are not only different in induction peak value but also in change trend. The gap has little effect on the surface electric and magnetic fields of the aircraft, but the influence is particularly obvious inside the aircraft. The gap of the aircraft has a great influence on the induced current of the cable. Compared with the model with a gap, the single wire induced current peak of the model with no gap decreased by 1 000 times, and the current peak of the coaxial wire decreased by 15 times.[Conclusions] The research results of this paper can provide references for understanding the electromagnetic effect of lightning strikes on aircraft, and the results will be helpful for carrying out the next step in lightning protection work.

According to the geometric characteristics of the elliptical gear,with different eccentricity ratio of ellipse,the different transmission ratio curve is got,and then the variable speed motion of pumping unit is completed. By using the Solid Works,the 3D modeling and motion simulation of the pumping unit are completed,and by using MATLAB,the digital simulation of the elliptical gear pumping unit is completed. Comparing with the suspension point velocity and acceleration between the ordinary pumping unit and the elliptical gear pumping unit,it is finally verified that the motion performance of the pumping unit is improved by using elliptical gear to the pumping unit,which reduces the vibration impact and the energy consumption.

After analyzing series monitoring data of micro-seismic and powered support pressure in Xinjiang,rock-burst mechanism was obtained. Thick and hard roof is main pressure source of rock-burst. Bad and delayed supporting make roof pressure transferred on coal-wall ahead of mining face. Thus, elastic energy and stress concentration formed, and fast mining speed aggravates energy and stress concentration degree. In this instance, rock-burst is inevitable because of strong burst liability of coal-seam. Based on this, rock-burst prevention principle was established that avoiding transferring hard and thick roof pressure to coal-wall. The prevention methods included broken blasting of hard roof, pressure-relief blasting of coal-body and increasing setting load of powered supports. The practice shows that prevention methods are effective. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of heat exposure during the second week of pregnancy on placental development and intrauterine growth of fetal rats., Methods: 24 pregnant rats were either exposed or not to a temperature of 35∓1 degrees celsius; during the second week of pregnancy. The body weight gain of the pregnant rats was measured regularly, and in late pregnancy, the pregnant rats were dissected and the number, weight, length, tail length, appearance of the offspring rats, number of live and still births, and the placental weight were recorded. The expressions of HSP70, Bax and Bcl-2 in the placenta were determined., Results: Compared with the control group, the pregnant rats in heat exposure group had significantly lower body weight at the end of pregnancy and gestational weight gain, and the body weight, body length and tail length of the offspring rats were also significantly lower or smaller (P<0.05). The placental weight was comparable between the two groups. The placental expressions of HSP70,Bax,and Bcl-2 were significantly higher in the heat exposure group than in the control group (P<0.05)., Conclusion: Heat exposure during the second trimester of pregnancy has adverse effects on placental development and intrauterine growth of the fetal rats by inducing heat shock response of placental tissue and apoptosis of the placental cells.

Objective: To investigate the integrated effects of adipocytes on rat beta-cells, differentiated 3T3L1 adipocytes and rat islet cells co-culture system was established., Methods: There were two groups: control group (SD rat islet cells) and co-culture group (islet cells and 3T3L1 adipocytes coculture system). Islet cells were obtained for determination of (1) insulin secretion and insulin content; (2) mRNA expressions of GLUT2, GCK and Kir6.2; (3) protein expressions of IR-beta, IRS-1 and their tyrosine phosphorylation level., Results: (1) At low glucose, insulin secretion of co-culture group increased compared with that of control group (0.79 +/- 0.35) ng x h(-1) x ml(-1) islet vs. (0.38 +/- 0.09) ng x h(-1) x ml(-1) x islet, P = 0.028. At high glucose, insulin secretion of those two groups was almost at the same level (P = 0.760). Compared with control group (2.84 +/- 0.92), stimulation index (SI, insulin release at high glucose/ low glucose) of co-culture system decreased to (1.57 +/- 0.61, P = 0.04). And the insulin content of the both groups was almost at the same level (P = 0.102). (2) The mRNA of GCK, GLUT2 and Kir6.2 in co-culture group downregulated to (0.27 +/- 0.11, P = 0.01), (0.34 +/- 0.24, P = 0.009) and (0.41 +/- 0.09, P = 0.003) compared with control group (mRNA = 1). (3) The protein levels of IR-beta, IRS-1 and their tyrosine phosphorylation decreased in co-culture system., Conclusions: 3T3L1 adipocytes are involved in beta-cell dysfunction, which may facilitate the development of type 2 diabetes. The effects may be mediated by multiple pathways, which include downregulation of GSIS related gene expressions and suppression of islet cell insulin signaling.

Objective: To investigate the association between serum uric acid (UA) and early kidney damage and the prevalence of early kidney damage [89 >or= GFR >or= 60 ml * min(-1) * (1.73m(2))(-1)] in the middle-aged and elders with normal serum creatinine., Methods: A survey of cardiovascular risk factors, including serum UA and estimated glomerular filtration rate (eGFR) [according to MDRD (modification of diet in renal disease) equation], was carried out in a local general population of Chengdu. A total of 1023 subjects with normal serum creatinine [mean age: (63 +/- 6) years; male: female = 52.7%: 47.3%] were recruited by random sampling method. The subjects were divided into 4 groups (A, B, C, D) according to the quartiles of serum UA levels (A: UA < 282 micromol/L, B: 282 micromol/L or= 379 micromol/L)., Results: In the group, the prevalence of early kidney damage was 28.1% (men: 35.8% > women: 19.5%, P < 0.01). In men and women, serum UA and mild kidney dysfunction were negatively correlated, and the prevalence of early kidney damage significantly increased with the elevated level of serum UA. The prevalence of early kidney damage was higher in men than women (P < 0.01). According to the logistic regression analysis adjusting for age, gender, waist, body mass index, triglyceride, HDL-C, total cholesterol, history of hypertension and diabetes type 2, the odds ratio of the prevalence of early kidney damage were 1.0 [B: 1.740 (P = 0.151), C: 3.599 (P = 0.01) and D: 5.488 (P < 0.01) respectively]., Conclusion: In the middle-aged and elders with normal serum creatinine, serum UA and eGFR are negatively correlated. And serum UA level is independently associated with early kidney damage.

Objective: To study the effects of 16-multi-detector row CT (MDCT) aortography with lower tube current in diagnosis of aortic diseases., Methods: The study was conducted in 2 steps. In the first step, 58 patients with suspicious aortic disease or after operation on the aorta underwent 16-MDCT aortography for 70 times. Ten of them underwent scanning with conventional tube current of 175 mAs and the other 60 patients were divided into 3 groups according to their bogy weights: <65 kg group (n=20) receiving the lowest tube current of 25 mAs, 65-75 kg group (n=20) receiving the lowest tube current of 50 mAs, and >75 kg group (n=20) receiving the lowest tube current of 75 mAs. In the second step 60 patients with dissecting aneurysm, underwent 16-MDST aortography and were divided into 3 groups according to their body weight too: <65 kg group (n=20) receiving the lowest tube current of 50 mAs, 65-75 kg group (n=20) receiving the lowest tube current of 75 mAs, and >75 kg group (n=20) receiving the lowest tube current of 100 mAs, all 25 mAs more compared with the corresponding groups in the first step. The weighted CT dose index (CTDI), scanning length, and dose length produce (DLP) were recorded. The diagnostic accuracy rates of the images from the low dose groups were compared with those of the higher dose groups., Results: The data of the first step showed that the CTDI values of the patients who received 25 mAs, 50 mAs, and 75 mAs tube current were 11.3%, 29.0%, and 42.7% that of the conventional tube current group (all P < 0.001) and the DLP values of the 3 low dose groups were also significantly lower than that of the conventional tube current group (all P < 0.001). The diagnostic accuracy rate of the 25 mAs, 50 mAs, and 75 mAs groups were 60% , 85%, and 85% that of the conventional tube current group. The results of the second step showed that the CTDI values of the 50 mAs, 75 mAs, and 100 mAs groups were 29.0%, 42.7%, and 57.3% that of the conventional tube current group respectively, and the DLP values of the 3 low dose groups were also significantly lower than that of the conventional group ( all P < 0. 001); and the 50 mAs, 75 mAs, and 100 mAs groups all showed good three-dimensional reconstruction imaging qualities, all with the diagnostic accuracy rate of 100%. The crossing section and three-dimensional images all showed excellent diagnostic image quality., Conclusion: 16-MDCT aortography with the tube current at the doses 50 mAs to 100 mAs suffices to diagnose aortic diseases in patients with different body weights. Higher tube current should be used in dissecting aneurysm. The tube current at the dose of 100 mAs satisfies the imaging and diagnosing of all kinds of aortic diseases in the patients with any body weight.

Objective: To study the effect of adriamycin combined with hyperthermia on tumor formation and growth of human B lymphoma cell line (Raji) in nude mice., Methods: Twenty-four BALB/C nude mice were divided into control group (37 degrees celsius;), chemotherapy group (37 degrees celsius;+ADM), hyperthermia group (42 degrees celsius;) and thermochemotherapy group (42 degrees celsius;+ADM), and in each mouse, 5 x 10(6) Raji cells were injected subcutaneously. The time and rate of tumor formation were observed, the tumor diameter was measured every 3 days and the tumor volume calculated to obtain the growth curves of the tumors. Three weeks after tumor formation, all the mice were executed to observe the histopathological changes of the tumor with HE staining., Results: The time of tumor formation in the control, chemotherapy, hyperthermia and thermochemotherapy groups were 11.2-/+1.7, 20.2-/+2.3, 15.3-/+1.6 and 23.8-/+1.7 days, respectively. Three weeks after tumor formation, the average weight of the tumors were 3.33-/+0.57, 2.26-/+0.28, 2.76-/+0. 26 and 1.73-/+0. 33 g, respectively, and the tumor growth inhibition rate was 48.0% in the thermochemotherapy group., Conclusion: Thermochemotherapy can be effective in inhibiting tumor growth and provides an alternative of adjuvant therapy for malignant B cell lymphoma.