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Coordination of Na2SnO3 with trace carboxymethyl chitosan contributes to standby protection and high utilization efficiency of the AZ61 anode.

Lichang Chen,1,&ast; Lingling Wu,1,&ast; Dongzhu Lu,1 Mei Zi,2 Huapeng Yu1 1Department of Respiratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, People’s Republic of China; 2Department of Respiratory and Critical Care Medicine, The Third People’s Hospital of Shenzhen, Shenzhen, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Huapeng YuDepartment of Respiratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, 510220, People’s Republic of ChinaTel +86 020 61643175Fax +86 020 84306143Email huapengyu@aliyun.comPurpose: To evaluate the contribution of fractional exhaled nitric oxide (FeNO) and impulse oscillometry (IOS) and spirometric parameters in predicting bronchial hyperresponsiveness (BHR) in adults with chronic cough.Patients and Methods: In total, 112 patients with chronic cough were enrolled in this prospective diagnostic study. Receiver operating characteristic (ROC) curves were generated to assess the diagnostic efficiency and optimal cut-off values of FeNO and IOS and spirometric parameters in predicting BHR. Optimal combinations of FeNO and IOS and spirometric parameters for BHR prediction were investigated using univariate and multivariate logistic regression models. Bootstrapping was employed for internal validation. Model discrimination and calibration were assessed using indices and calibration plots.Results: Rhinitis and values of FeNO, IOS parameters (resonant frequency (Fres), reactance at 5 Hz (X5), and integrated area of low-frequency X (AX)) and spirometric parameters (FEV1, PEF, MEF75, MEF50, MEF25, MMEF) were significantly different between patients with BHR and those without BHR (P < 0.05). After adjusting for rhinitis, logistic analyses showed that FeNO combined with Fres, FeNO combined with MMEF, or the combination of FeNO, Fres and MMEF had high predictive value in diagnosing BHR; the areas under the ROC curves (AUCs) of the corresponding three models were 0.914, 0.919 and 0.927, respectively. In addition, the three models displayed good discrimination, with high C-index values and good calibration.Conclusion: FeNO combined with Fres or MMEF or a combination of these three parameters may be conveniently used as indicators in BHR prediction.Keywords: maximum mid-expiratory flow, resonant frequency, cough variant asthma, ROC curve, diagnosis

The corrosion behavior of Mg-Nd binary alloys in the harsh South China Sea environment was researched by scanning electron microscopy, energy-dispersive spectrometry and X-ray diffraction analysis. In order to explain the corrosion mechanism, corrosion resistance was analyzed by weight loss rate and electrochemical measurement in the laboratory. With a continuous enlargement of Nd-content, Mg12Nd phases increased and multiplied. The weight loss rate of Mg-0.5Nd alloy was 0.0436 mg•cm−2•y−1 (0.0837 mm•y−1), whereas that of Mg-1.5Nd alloy was 0.0294 mg•cm−2•y−1 (0.0517 mm•y−1) during the exposure corrosion in the South China Sea site. The mechanical strength of Mg-1.5Nd alloy was 148 MPa before the exposure in the harsh marine environment, while the residual mechanical strength was merely about 94 MPa after the exposure test. Both Mg-1.5Nd alloy and Mg-1.0Nd alloy occurred the brittle fracture, which resulted that the elongation was nearly equal to zero. The self-corrosion current density demonstrated that degradation rate of Mg-Nd binary alloys was as follows : Mg-0.5Nd>Mg-1.0Nd>Mg-1.5Nd. For the South China Sea corrosion site, a large amount of sea salts exited in the atmospheric environment. Due to the heavy rainfall and high humidity, sodium chloride in the atmospheric environment dissolved, more serious electrochemical corrosion occurred on the surface of Mg-Nd binary alloys.

The atmospheric corrosion of iron and steels not only affects the safety of infrastructures but also destroys the appearances and ornamental appreciations. The corrosivity of an environment can suggest such information that is useful for corrosion protection design and maintenance. The classical exposure test method is applicable to the evaluation of atmospheric corrosivity, but it takes a long time and can’t tell the evolution of corrosivity over a period of time. Atmospheric corrosion monitor (ACM) has been proved to be an effective method to investigate the corrosivity of atmospheric environment. However, unfortunately, the experiences of the authors of this paper show that the output by measuring current is interfered by the noise when the sensor is dry, and it is often difficult to differentiate it from the background signals, while the corrosion process is still going on the sensor surface. In this paper, a Fe-Zn ACM sensor was modified by connecting a larger resistor in parallel and measuring the electromotive force. Laboratory experiments and field tests revealed the influence of temperature, RH and rainfall on the ACM outputs, verifying the applicability of the modified sensor for the monitoring of the corrosivity variations in a region.

The corrosion behaviour of high-strength low-alloy AISI 4135 steel was studied in the presence of homoacetogenic bacteria (Blautia coccoides GA-1), which catalyse the formation of acetate from H-2 plus CO2 in their energy metabolism. In addition, the effects of cathodic protection were studied. The chronoamperometry curves showed a negative current density. The minimum current density was approximately -1.5 mu A.cm(-2). The results revealed that the strain GA-1 could consume 'cathodic hydrogen' and promote the cathodic reaction of AISI 4135 steel, but the hydrogen consumption of strain GA-1 was not the main reason leading to the increase in the corrosion current density.

Microbiologically influenced corrosion caused by sulfate-reducing bacteria (SRB) poses a serious threat to marine engineering facilities. This study focused on the interaction between the corrosion behavior of two aluminum alloys and SRB metabolic activity. SRB growth curve and sulfate variation with and with aluminum were performed to find the effect of two aluminum alloys on SRB metabolic activity. Corrosion of 5052 aluminum alloy and Al-Zn-In-Cd aluminum alloy with and without SRB were performed. The results showed that both the presence of 5052 and Al-Zn-In-Cd aluminum alloy promoted SRB metabolic activity, with the Al-Zn-In-Cd aluminum alloy having a smaller promotion effect compared with 5052 aluminum alloy. The electrochemical results suggested that the corrosion of the Al-Zn-In-Cd aluminum alloy was accelerated substantially by SRB. Moreover, SRB led to the transformation of Al-Zn-In-Cd aluminum alloy corrosion product from Al(OH)3 to Al2S3 and NaAlO2.

We aimed to explore whether large airway remodeling and small airway structural changes exist in subjects with small airway asthma phenotype and to evaluate the relationships between quantitative high-resolution computed tomography (qHRCT) parameters and lung function.We enrolled 15 subjects with small airway asthma phenotype and 18 healthy controls. The two groups were matched by age, sex and body square area (BSA) with propensity score matching (PSM). Pulmonary function and qHRCT parameters [wall thickness (WT), wall area (WA), lumen area (LA), wall area percentage (WA%) of the 4th-6th generations in the right upper lobe apical segmental bronchus (RB1), adjusted by BSA, WT/BSA, WA/BSA, and LA/BSA, relative volume change -860 HU to -950 HU (RVCThe small airway asthma phenotype had significantly higher WA%, RVCCombining physiological tests with imaging approaches can lead to better evaluation of small airway disfunction (SAD) in asthmatic patients. Additionally, despite nonexistent airflow obstruction in patients with small airway asthma phenotype, large airway remodeling and small airway structural changes may appear simultaneously in the early stage of disease.

Purpose To evaluate the value of impulse oscillometry (IOS) and quantitative HRCT parameters for differentiating asthma-COPD overlap (ACO) in COPD patients. Patients and Methods We enrolled 44 controls and 66 COPD patients, divided into the pure COPD group (n=40) and the ACO group (n=26). Spearman correlation analysis was utilized to assess the relationship between the quantitative HRCT and IOS parameters. A binary logistic regression analysis was performed to analyze the associations between the different variables and the risk of ACO. Receiver operating characteristic (ROC) curves were employed to identify the optimal cutoff and assess the diagnostic value of relative volume change -856 HU to -950 HU (RVC-856 to -950), decrease in the resistance from 5 Hz to 20 Hz (R5-R20) and their combination in predicting ACO. Bootstrapping validation was used to evaluate the internal validation. The concordance index (C-index) and calibration plot were calculated to assess the discrimination and calibration of the prediction model. Results Binary logistic regression analysis indicated that RVC-856 to -950 and the IOS parameters (R5-R20, R5, X5) were independently correlated with a higher risk of developing ACO after adjusting for age, sex, body mass index (BMI), history of smoking, exacerbation and atopy or allergic rhinitis. A correlation analysis showed a good correlation between the pulmonary function parameters and RVC-856 to -950, with a weaker correlation with the % area of low attenuation (LAA%) in ACO patients. Combining RVC-856 to -950 and R5-R20 to predict ACO, the AUC was 0.909, and the optimal cutoff value was >-0.62 for RVC-856 to -950 and >0.09 for R5-R20. Good calibration and favorable discrimination were displayed with a higher C-index. Conclusion More serious small airway impairment exists in ACO patients. The combination of RVC-856 to -950 and R5-R20 could be applied to differentiate ACO from COPD patients.

MgO films would naturally form on a magnesium alloy matrix in the air. They are loose and porous, and the corrosion resistance of magnesium alloys is limited. Here, we demonstrate that such a loose MgO film is not merely useless in the protection of magnesium alloys, as metallic atoms could penetrate the MgO film to form intermetallic coatings on the magnesium alloy matrix. In this work, utilizing a diffusion source which contains ZnO and NH4Cl, an intermetallic layer was obtained on a magnesium alloy. The morphology and chemical composition of the intermetallic layer and the MgO film were analyzed. Results show that Mg atoms in the magnesium alloy could be utilized as a reductive agent to reduce ZnO into Zn atoms, as reduced Zn atoms are able to penetrate the loose MgO film and form a Zn-rich intermetallic layer on the magnesium alloy matrix. The concept that the MgO film could be utilized as a potential path for the surface alloying of magnesium alloys would not only deepen the understanding of the natu...

There are various methods available to enhance the corrosion resistance of magnesium alloys. Here, through utilising microstructure observations and phase identification, we show that, even with stable alumina, magnesium alloys can have their surface strengthened. Active magnesium atoms can be utilised to reduce the alumina and produce aluminum atoms. Aggregation of aluminum atoms on the magnesium alloy surface leads to an Al-rich intermetallic layer, which could enhance the corrosion resistance of the magnesium alloy. This is a new approach to protect magnesium alloys which takes advantage of the activity of magnesium atoms to fabricate protective coatings.

The application of high-strength steels in marine engineering is gaining importance because of their high performance and ability to help save resources. However, detailed and systematic information about the corrosion behavior of high-strength steels in different marine corrosion zones is still limited. This study aimed to investigate and compare the corrosion behavior of AISI 4135 high-strength steel in marine atmospheric, splash, tidal, and immersion zones, focusing on rust layer characteristics, corrosion form and electrochemical corrosion behavior. Corrosion exposure experiments were performed in a specific sea area, and the recovered steel samples were characterized by Raman spectroscopy, confocal laser scanning microscopy, nitrogen adsorption analysis, etc. Results showed that the rust layer formed on the surface of the steel in all corrosion zones had component delamination. The steel samples in the atmospheric, splash, and tidal zones were characterized by pitting corrosion, where the average depths of the corrosion pits were 56.1 ± 4.7 μm, 199.5 ± 12.6 μm, 108.1 ± 11.0 μm, respectively, whereas those in the immersion zone were characterized by general corrosion. Meanwhile, electrochemical tests were performed on the electrode samples during exposure. Results showed that the corrosion of the steel progressed from slow to fast in the atmospheric, splash, and tidal zones, whereas it was relatively steady in the immersion zone. Differentiated models of the corrosion evolution of steel under wet-dry cycle and immersion conditions were presented. This discrepancy is related to the varying degrees of accumulation of ionic corrosion products at the metal/oxide interface, which are determined by the mean pore access diameter of the rust layer and the corrosion environment. This study is highly significant for the design of marine engineering considering the safety applications of high-strength steel structures in harsh marine environments.

Wei Cheng,1,* Lichang Chen,1,* Huapeng Yu,1 Dongzhu Lu,1 Rong Yu,1 Jian Chen2 1Department of Respiratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, People’s Republic of China; 2Department of Neurology, Zhujiang Hospital, Southern Medical University, Guangzhou, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jian ChenDepartment of Neurology, Zhujiang Hospital of Southern Medical University, No. 253, Industrial Avenue, Guangzhou, Guangdong, 510280, People’s Republic of ChinaTel +86 18665000975Fax +86 02062783083Email smuchenjian@163.comPurpose: To evaluate the value of the NLR (neutrophil-to-lymphocyte ratio) and the fibrinogen level in predicting stroke-associated pneumonia (SAP) in acute ischemic stroke (AIS) patients.Patients and Methods: In total, we enrolled 734 medical-ward patients with AIS in this retrospective study. Patients were divided into SAP (n=52) and non-SAP (n=682) groups according to the diagnostic criteria of SAP. Binary logistic regression analysis was used to analyze the relationship between the NLR, serum fibrinogen concentration and SAP. Receiver operating characteristic (ROC) curves were generated to identify the optimal cutoff points and assess the diagnostic value of the NLR, serum fibrinogen and the combination of NLR and fibrinogen in predicting SAP.Results: SAP occurred in 52 (7.08%) patients among the enrolled AIS patients. Binary logistic regression analysis showed that the NLR (odds ratio [OR]: 2.802, 95% confidence interval [CI]: 1.302– 6.032, P=0.008) and serum fibrinogen concentration (OR: 7.850, 95% CI: 3.636– 16.949, P=0.000) were independently associated with a higher risk of SAP incidence after adjusting for age, sex, ASPECT score, atrial fibrillation, nasogastric tube feeding, LDL-C and TC, temperature at admission and mechanical ventilation. The optimal cutoff points of the NLR and serum fibrinogen to distinguish SAP among AIS patients were 3.603 (AUC, 0.690; NPV, 95.78; PPV, 19.01) and 4.595 (AUC, 0.727; NPV, 95.60; PPV, 24.49), respectively. When the combination of NLR and fibrinogen was used to predict SAP, the optimal cutoff points were > 2.436 for NLR and > 3.24 for fibrinogen (AUC, 0.758; NPV, 98.50; PPV, 11.80).Conclusion: The NLR and serum fibrinogen might have greater negative diagnostic value in predicting SAP among AIS patients. Combining the NLR and serum fibrinogen showed an increased AUC for predicting SAP among AIS patients.Keywords: stroke-associated pneumonia, neutrophil-to-lymphocyte ratio, fibrinogen, receiver operating characteristic curve

Most studies on the corrosion inhibition performance of organic molecules and (nano)materials were conducted within “carbon steel/1.0 M HCl” solution system using similar experimental and theoretical methods. As such, the numerous research findings in this system are sufficient to conduct comparative studies to select the best-suited inhibitor type that generally refers to a type of inhibitor with low concentration/high inhibition efficiency, nontoxic properties, and a simple and cost-economic synthesis process. Before data collection, to help readers have a clear understanding of some crucial elements for the evaluation of corrosion inhibition performance, we introduced the mainstay of corrosion inhibitors studies involved, including the corrosion and inhibition mechanism of carbon steel/HCl solution systems, evaluation methods of corrosion inhibition efficiency, adsorption isotherm models, adsorption thermodynamic parameters QC calculations, MD/MC simulations, and the main characterization techniques used. In the classification and statistical analysis section, organic compounds or (nano)materials as corrosion inhibitors were classified into six types according to their molecular structural characteristics, molecular size, and compound source, including drug molecules, ionic liquids, surfactants, plant extracts, polymers, and polymeric nanoparticles. We outlined the important conclusions obtained from recent literature and listed the evaluation methods, characterization techniques, and contrastable experimental data of these types of inhibitors when used for carbon steel corrosion in 1.0 M HCl solution. Finally, statistical analysis was only performed based on these data from carbon steel/1.0 M HCl solution system, from which some conclusions can contribute to reducing the workload of the acquisition of useful information and provide some reference directions for the development of new corrosion inhibitors.

The corrosion behavior and mechanical property of Mg-7Y-x Nd (x = 0.5, 1.0, 1.5 wt%) alloys were investigated. The microstructure and precipitations of Mg-7Y-x Nd alloys were studied by scanning electron microscopy, energy-dispersive spectrometry and X-ray Diffraction. The quantities of the Mg-12 (Y, Nd) phase increased, whereas that of the Mg-24 (Y, Nd) 5 phase decreased with increasing Nd-content. The weight loss rate decreased from 17.5020 mg cm(-2) d(-1) (36.7542 mm y(-1)) to 9.3744 mg cm(-2) d(-1) (19.6862 mm y(-1)). The electrochemical measurement also demonstrated the similar tendency. The loss in mechanical properties after corrosion reaction followed the order Mg-7Y-0.5Nd > Mg7Y- 1.0Nd > Mg-7Y-1.5Nd. The precipitations played dual roles in the corrosion resistance that depended on type and distribution. (c) 2018 Published by Elsevier B. V. on behalf of Chongqing University.

Titanium dioxide (TiO2) nanotube arrays coupled with a narrow gap semiconductor—bismuth selenide (Bi2Se3)—exhibited remarkable enhancement in the photocathodic protection property for 304 stainless steel under visible light. Bi2Se3/TiO2 nanocomposites were successfully synthesized using a simple two-step method, including an electrochemical anodization method for preparing pure TiO2 and a chemical bath deposition method for synthesizing Bi2Se3 nanoflowers. The morphology and structure of the composite films were studied by scanning electron microscopy, energy dispersion spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction. In addition, the influence of the Bi2Se3 content on the photoelectrochemical and photocathodic protection properties of the composite films was also studied. The photocurrent density of the Bi2Se3/TiO2 nanocomposites was significantly higher than that of pure TiO2 under visible light. The sensitizer Bi2Se3 enhanced the efficient separation of the photogenerated electron-hole pairs and the photocathodic protection properties of TiO2. Under visible light illumination, Bi2Se3/TiO2 nanocomposites synthesized by the chemical bath deposition method with Bi3+ (0.5 mmol/L) exhibited the optimal photogenerated cathodic protection performance for 304 stainless steel.

In order to develop a high durability building decoration zinc-based alloy materials, the as-cast Zn-1.0Cu-1.0Ti alloy (ZCT-AC) with homogeneous microstructure and high hardness was successfully prepared by induction melting and rapid solidification. Interestingly, almost all Ti element exists in the as-cast alloy in the form of the homogeneous strip-like TiZn16 phase, and the Cu element is uniformly dissolved in both the η-Zn and TiZn16 phase in the form of supersaturated solid solution. The hardness of the ZCT-AC alloy was about 79.3% and 52.7% higher than that of pure Zn and a commercial cold-rolled zinc‑titanium alloy (ZCT-CR), respectively. By potentiodynamic polarization tests in NaCl solution with four different mass fractions (0.1, 1.0, 3.5, and 5.0 wt%) at 25 °C and in 3.5 w.t% NaCl solution at four different temperatures (25, 35, 45, and 55 °C), ZCT-AC alloy showed higher corrosion resistance than the two control samples because of both a high formation efficiency and a high structural stability of passive film. Furthermore, Several plausible corrosion mechanisms of the three samples have been further studied systematically by a long-term immersion tests in 3.5 wt% NaCl solution, the results suggested that the corrosion process of ZCT-AC alloy was dominated by uniform corrosion which led to a higher interface uniformity, the corrosion layer of the alloy had higher uniformity and overall density, and the corrosion rate of both micro-galvanic corrosion and intergranular corrosion were inhibited significantly owing to the uniform distribution of Cu element. This study might provide a theoretical guidance for designing the high durability building decoration materials.

In order to promote the utilization of the powder thermal diffusion alloying method to protect magnesium alloys, effect of cooling rate as well as the original state of the magnesium alloy specimens including chemical composition and thickness on the as diffusion alloyed intermetallic layer was investigated. The results show that water quenched specimens could have dendritic crystals in the intermetallic layer even at a diffusion temperature lower than the Mg-Al eutectic temperature. Thinner specimens and higher Al content are preferred for the powder thermal diffusion alloying process. Morphology of the Mg17Al12 intermetallic layer with embedded α-Mg islands could be attributed to two main reasons, one is the decomposition of the unstable solution, and the other is liquid saturation and preferential diffusion at heterogeneous structures. Keywords: Magnesium alloy, Diffusion alloying, Intermetallic layer, Morphology, Dendritic crystal, Matrix

Compact powder diffusion alloying process has been carried out on AZ91D magnesium specimens at 430 °C in air atmosphere. After the sole diffusion alloying process, only partially alloyed surface was obtained, and this was attributed to the incomplete diffusion alloying process. Moreover, formation of the MgO film caused weight loss of the overall specimen, and the weight loss phenomenon is also related to the initiation and growth of cracks at edges and/or corners of some specimens. Repeated diffusion alloying processes after eliminating the MgO film and adding new diffusion source allowed the Al atom diffusion process to continue. By this method, a more complete intermetallic coating was obtained.

The groundwater will completely infiltrate to the surface of nuclear waste container after the closure of its deep geological disposal. Therefore, the corrosion behaviour of Q235 carbon steel, titanium and titanium alloy, which were the candidates as the container materials for high-level nuclear waste disposal in simulated groundwater solution of Beishan to be served as the preselected high-level nuclear waste disposal area in China at different temperatures, was studied through electrochemical methods including open circuit potential, electrochemical impedance spectroscopy and potentiodynamic polarisation curve measurements. The results show that the corrosion rate of titanium and titanium alloy is lower than that of carbon steel at all temperatures, and they are more promising as container materials. Another phenomenon is that higher temperatures facilitate the protection performance of corrosion products compared with lower temperatures.

The corrosion resistance of magnesium alloys could be enhanced by covering metallic coatings on the surface. The zinc-rich coating is one of these metallic coatings. To fabricate a zinc-rich coating on magnesium alloys, the substrate should be pretreated carefully, and a protective atmosphere is usually required. In this research, a zinc-rich coating was successfully fabricated on the AZ91D magnesium alloy in air by a diffusion alloying method, with zinc oxide as the zinc source. At the same time, the pretreatment of the magnesium alloy matrix was greatly simplified. The as-diffusion-alloyed zinc-rich intermetallic layer was investigated, utilizing SEM, EDS, and XRD, respectively. It is inferred that zinc oxide was reduced into Zn atoms by the active Mg atoms, and the Mg atoms were coming from the magnesium alloy matrix. Then the Zn atoms passed through the oxide film and formed an intermetallic layer on the magnesium alloy surface. Thus, taking advantage of the activity of Mg atoms, magnesium alloys could be surface alloyed with oxides.

Oxides can be utilized in various industries. They are frequently doped with other cations to improve some key properties. Although doping is common, the doping mechanism related to transport of doped metallic cations in the oxide grain on the atomic scale still needs to be clarified. Here, with MgO as a prototype, Zn cations in a polycrystalline MgO film was investigated utilizing microstructure observation and chemical composition analyses. Results show that although there are various defects such as vacancies, dislocations, voids, grain boundaries and impurity ions in the polycrystalline MgO film, a Zn cation could penetrate the overall polycrystalline MgO film. Although a Zn cation move relative randomly in an individual MgO grain, as there is a constant source and a constant sink for Zn located at opposite sides of the MgO film, the Zn cation could move directionally on a relatively macro scale from the source to the sink.

Effect of heat treatment on the hydrogen permeation behaviour of AISI 4135 steel was studied by electrochemical method under simulated splash zone conditions. The hydrogen permeation current reached maximum at dry stage and the amount of hydrogen permeated showing a maximum in sixth cycle. Moreover, it was found that the amount of hydrogen permeated through specimen with bainitic microstructure was lower than that in other specimens. The average value of charge transfer resistances for heat treated specimens A, B, C and D exhibit no significant differences under nature sea water film. Moreover, the heat treatments have no prominent impact on corrosion products from the X-ray diffraction (XRD) pattern and SEM analysis. Therefore, the differences in hydrogen permeation behaviours were mainly attributed to the microstructures of specimens other than the differences in corrosion behaviour.

Titanium is being considered as a candidate material for high-level nuclear waste container due to its superior corrosion resistance. However, problems may arise when titanium comes in contact with hydrogen-bearing environments, as it is vulnerable to hydrogen embrittlement. To assess the lifetime of titanium container, hydrogen content and hydrogen permeation efficiency were estimated in infiltrated water through bentonite prepared with simulated groundwater of Beishan, the preselected area in China, by electrochemical and metallurgical analysis. It is concluded that the absorbed hydrogen due to general corrosion will not be sufficient for hydrogen embrittlement to occur in titanium for at least 10,000 years after deep geological disposal. This represents more than 300 and 5,000 half-lives of Cs137 and Cs134 respectively; cesium being the most likely element to escape a repository due to its high solubility in groundwaters.

Corrosion is a ubiquitous and costly problem for a variety of industries. Understanding and reducing the cost of corrosion remain primary interests for corrosion professionals and relevant asset owners. The present study summarises the findings that arose from the landmark “Study of Corrosion Status and Control Strategies in China”, a key consulting project of the Chinese Academy of Engineering in 2015, which sought to determine the national cost of corrosion and costs associated with representative industries in China. The study estimated that the cost of corrosion in China was approximately 2127.8 billion RMB (~ 310 billion USD), representing about 3.34% of the gross domestic product. The transportation and electronics industries were the two that generated the highest costs among all those surveyed. Based on the survey results, corrosion is a major and significant issue, with several key general strategies to reduce the cost of corrosion also outlined. It is estimated that the effects of corrosion in China cost approximately $310 billion USD in 2014. Corrosion is a costly issue, justifying substantial expenditure into techniques to protect and mitigate susceptible metals from its effects, and research investment. China has seen rapid growth in its economy in recent times, driven in part by investment in industry. In order to understand the monetary impact of corrosion in China, The Chinese Academy of Engineering instigated a nationwide study led by the Institute of Oceanology, Chinese Academy of Sciences. It estimates that approximately $310 billion USD was lost to the consequences of corrosion and money spent addressing it in 2014, accounting for 3.34% of GDP. Transportation and electronics industries generated the highest costs. Several recommendations are made, including the need for a government-coordinated national strategy.

The purpose of this paper is to investigate heat dissipation performance of porous copper with long cylindrical pores fabricated by a unidirectional solidification method. Three samples with porosity of 29.87%, 34.47% and 50.98% were chosen and cut into size of 60 mm (length) × 26 mm (width) × 2 mm (thickness) along the vertical direction of pore axis. Their heat dissipation performance was evaluated by a nonsteady method in air and compared to those of not only bulk copper but also bored coppers with porosity of 30.61% and 32.20%. It is found that the porous copper dissipated heat faster by a forced air convection than that by natural convection from 80 °C to room temperature and both porosity and pore size play an important role in the performance for the porous copper. Furthermore, the heat dissipation rate is higher when the forced air was circulated along the specimens than that perpendicular to the specimens for the porous copper. It is revealed that porous copper with bigger porosity and a proper pore size possesses a higher heat dissipation rate. It is concluded that the porous copper with elongated cylindrical pores has larger heat dissipation performance than both the bulk copper and the bored copper, which is attributed to its higher specific surface area. Application of the porous copper for heat dissipation is promising.

The powder thermal diffusion alloying method could be utilized to fabricate Al-rich intermetallic coatings on magnesium alloys in the air. While the role of ammonium chloride powder in the diffusion alloying source is still to be investigated. This research took the AZ91D magnesium alloy as the substrate. Diffusion sources with various powders were utilized as the diffusion source. Microstructure observation and phase identification were enrolled to investigate the role of the ammonium chloride powder in the diffusion alloying process. Results indicate that HCl gas could turn some solid Al powder into gaseous AlCl3 to enhance the transport of active Al atoms, moreover, it reacts with the dense MgO film and converts it to a loose one, which enables the AlCl3 gas to penetrate MgO and arrive the matrix to form a protective coating. Furthermore, the ammonium chloride content should be confined to 10 wt. % of the diffusion alloying source. Too much ammonium chloride powder would result in a worse intermetallic coating.

Aquaporin-1 (AQP-1), a six-transmembrane domain protein, is found to be responsible for water transport. The purpose of this study was to investigate the expression of AQP-1 mRNA and protein in the testis, epididymis, vas deferens, ventral prostate, and seminal vesicle from mature mice by using reverse transcription polymerase chain reaction (RT-PCR) and Western blotting, and the cellular localization of AQP-1 by immunohistochemistry. RT-PCR revealed that AQP-1 mRNA was expressed in all organs we examined. Western blotting displayed a 29-kDa band and a 35- to 45-kDa band corresponding to non-glycosylated and/or glycosylated AQP-1 in those organs. The immunohistochemical evidence showed that AQP-1 was mainly located on the plasma membrane of epithelial cells of the rete testis, vas deferens, ventral prostate, seminal vesicle and the non-ciliated cells of the proximal and distal efferent ducts. However, AQP-1 was absent from spermatogenic cells lining the seminiferous epithelium and from the spermatozoa in the lumen of the distal efferent duct. These findings provide valuable information on the expression of AQP-1 in male reproductive organs and suggest that AQP-1 is involved in water transport to regulate water homeostasis in male reproductive physiology.