Two Birds with One Stone: Broadband Electromagnetic Wave Absorption and Anticorrosion Performance in 2-18 GHz for Prussian Blue Analog Derivatives Aimed for Practical Applications.

Nowadays, the exploration of electromagnetic (EM) wave absorbers with anticorrosion to improve the survivability and environmental adaptability of military targets in the harsh environments is becoming an attractive and unavoidable challenge. Herein, through modulation of the metal composition in the precursors, the core@shell structure Prussian blue analog-derived NiCo@C, CoFe@C, NiFe@C, and NiCoFe@C are obtained with excellent EM wave absorption performance. As for NiCoFe@C, ascribed to the coupling effect of the dual magnetic alloy, a minimum reflection loss (RL) of -47.6 dB and an effective absorption bandwidthof 5.83 GHz are realized, which cover the whole Ku-band. Meanwhile, four absorbers display the lower corrosion current density (10-4 -10-6 A cm-2 ) and larger polarization resistance (104 -106  Ω) under acid, neutral, and alkaline corrosion conditions over uninterrupted 30 days. Furthermore, due to the spatial barrier effect and the passivation effect of the graphitic carbon shell , the continuous salt spray test has little effect on RL performance and inconspicuously changes the surface morphologies of coating, demonstrating its excellent bifunctional performance. This work lays the foundation for the development of metal-organic frameworks-derived materials with both anticorrosion and EM wave absorption performance.

Contrasting environmental factors drive local adaptation at opposite ends of an environmental gradient in the yellow monkeyflower (Mimulus guttatus).

PREMISE: Identifying the environmental factors responsible for natural selection across different habitats is crucial for understanding the process of local adaptation in plants. Despite its importance, few studies have successfully isolated the environmental factors driving local adaptation in nature. In this study, we evaluated the agents of selection responsible for local adaptation of the monkeyflower Mimulus guttatus to California's coastal and inland habitats. METHODS: We implemented a manipulative reciprocal transplant experiment at coastal and inland sites, where we excluded aboveground stressors in an effort to elucidate their role in the evolution of local adaptation. RESULTS: Excluding aboveground stressors, most likely a combination of salt spray and herbivory, completely rescued inland annual plant fitness when transplanted to coastal habitat. The exclosures in inland habitat provided a benefit to the performance of coastal perennial plants. However, the exclosures are unlikely to provide much fitness benefit to the coastal plants at the inland site because of their general inability to flower in time to escape from the summer drought. CONCLUSIONS: Our study demonstrates that a distinct set of selective agents (aboveground vs. belowground) are responsible for local adaptation at opposite ends of an environmental gradient.

Corrosion Measurement of the Atmospheric Environment Using Galvanic Cell Sensors.

An atmospheric corrosion monitor (ACM) is an instrument used to track the corrosion status of materials. In this paper, a galvanic cell sensor with a simple structure, flexible parameters, and low cost was proposed for constructing a novel ACM, which consisted of three layers: the upper layer was gold, used as the cathode; the lower layer was corroded metal, used as the anode; and the middle layer was epoxy resin, used to separate the cathode and anode. Typically, the anode and epoxy resin were hollowed out, and the hollow parts were filled with electrolyte when it was wet to form a corrosive galvanic cell. Specifically, the corrosion rate was obtained by measuring the short circuit current of the cell. The sensor was made of a printed circuit board (PCB) or flexible printed circuit (FPC) and a metal coupon, which allowed for early control of the electrical parameters (including sensitivity and capacity) and could be combined with various metals. Additionally, the sensor feasibility was studied in water droplet experiments, during which the corrosive current changed with the electrolyte evaporation. The sensor practicability was also verified in a salt spray test, and the electric charge was compared using the thickness loss of bare coupons. A contrast test was also conducted for the corrosivity of different sensors made of aluminum, iron and copper.

Enhanced Long-Term Corrosion Resistance of 316L Stainless Steel by Multilayer Amorphous Carbon Coatings.

Diamond-like carbon (DLC) coatings are effective in protecting the key components of marine equipment and can greatly improve their short-term performance (1.5~4.5 h). However, the lack of investigation into their long-term (more than 200 h) performance cannot meet the service life requirements of marine equipment. Here, three multilayered DLC coatings, namely Ti/DLC, TiCx/DLC, and Ti-TiCx/DLC, were prepared, and their long-term corrosion resistance was investigated. Results showed that the corrosion current density of all DLC coatings was reduced by 1-2 orders of magnitude compared with bare 316L stainless steel (316Lss). Moreover, under long-term (63 days) immersion in a 3.5 wt.% NaCl solution, all DLC coatings could provide excellent long-term corrosion protection for 316Lss, and Ti-TiCx/DLC depicted the best corrosion resistance; the polarization resistances remained at ~3.0 × 107 Ω·cm2 after immersion for 63 days, with more interfaces to hinder the penetration of the corrosive media. Meanwhile, during neutral salt spray (3000 h), the corrosion resistance of Ti/DLC and TiCx/DLC coatings showed a certain degree of improvement because the insoluble corrosion products at the defects blocked the subsequent corrosion. This study can provide a route to designing amorphous carbon protective coatings for long-term marine applications in different environments.

Corrosion Behavior of Homogenized and Extruded 1100 Aluminum Alloy in Acidic Salt Spray.

The 1100 aluminum alloy has been widely used in many industrial fields due to its high specific strength, fracture toughness, excellent thermal conductivity, and corrosion resistance. In this study, the corrosion behavior of the homogenized and hot-extruded 1100 aluminum alloy in acid salt spray environment for different time was studied. The microstructure of the 1100 aluminum alloy before and after corrosion was characterized by an optical microscope (OM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and a laser scanning confocal microscope (LSCM). The difference in corrosion resistance between the homogenized and extruded 1100 aluminum alloy was analyzed via the electrochemical method. The results indicate that after hot extrusion at 400 °C, the microstructure of the 1100 aluminum alloy changes from an equiaxed crystal structure with (111) preferentially distributed in a fibrous structure with (220) preferentially distributed. There was no obvious dynamic recrystallization occurring during extrusion, and the second-phase particles containing Al-Fe-Si were coarse and unevenly distributed. With the increase in corrosion time, corrosion pits appeared on the surface of the 1100 aluminum alloy, and a corrosion product layer was formed on the surface of the homogenized 1100 aluminum alloy, which reduced the corrosion rate. After 96 h of corrosion, the CPR of the extruded samples was 0.619 mm/a, and that of the homogenized samples was 0.442 mm/a. The corrosion resistance of the extruded 1100 aluminum alloy was affected by the microstructure and the second phase, and no protective layer of corrosion products was formed on the surface, resulting in a faster corrosion rate and deeper corrosion pits.

Corrosion Behavior and Mechanical Property of 5182 Aluminum/DP780 Steel Resistance Spot Welding Joints.

Corrosion behavior is critical to the application of lightweight aluminum/steel joints using new resistance spot welding (RSW) technology. The study investigated the corrosion mechanism and the shear strength of RSW joints comprising 1.2 mm 5182 aluminum and 1.5 mm DP780 galvanized steel. Electrochemical corrosion tests were conducted on the base materials and various positions of the welds in a 3.5% NaCl solution. This result revealed that the corrosion susceptibility of the interfacial intermetallic compound (IMC) layer was not accelerated by the aluminum nugget because of the noble corrosion potential. Subsequently, the spray acceleration test was employed to investigate the corrosion mechanism. It is noteworthy that microcracks, as well as regions enriched with silicon and oxygen at the interface front, are preferential to corrosion during salt spray exposure, instead of the IMC layer. Moreover, the shear strength of the joints decreases with the reduction in the effective joint area after the salt spray exposure of the weld joints. This research systematically explored the corrosion behavior and its relationship with the mechanical properties of Al alloy/steel RSW joints.

Corrosion Behavior of 10 ppi TAD3D/5A05Al Composite in a Chloride Environment.

This study utilizes desalted and denitrated treated aluminum dross (TAD) as a raw material, along with kaolin and 10 ppi (pores per inch) polyurethane foam as a template. The slurry is converted into an aluminum dross green body with a three-dimensional network structure using the impregnation method. A three-dimensional network aluminum dross ceramic framework (TAD3D) is created at a sintering temperature of 1350 °C. The liquid 5A05 aluminum alloy at a temperature of 950 °C infiltrates into the voids of TAD3D through pressureless infiltration, resulting in TAD3D/5A05Al composite material with an interpenetrating phase composite (IPC) structure. The corrosion behavior of TAD3D/5A05 composite material in sodium chloride solution was examined using the salt spray test (NSS) method. The study shows that the pores of the TAD3D framework, produced by sintering aluminum dross as raw material, are approximately 10 ppi. The bonding between TAD3D and 5A05Al interfaces is dense, with strong interfacial adhesion. The NSS corrosion time ranged from 24 h to 360 h, during which the composite material underwent pitting corrosion, crevice corrosion and self-healing processes. Results from Potentiodynamic Polarization (PDP) and Electrochemical Impedance Spectroscopy (EIS) indicate that, as corrosion progresses, the Ecorr of TAD3D/5A05Al decreases from -0.718 V to -0.786 V, and Icorr decreases from 0.398 µA·cm-2 to 0.141 µA·cm-2. A dense oxide film forms on the surface of the composite material, increasing the anodic Tafel slope and decreasing the cathodic Tafel slope, thus slowing down the rates of cathodic and anodic reactions. Factors such as lower interface corrosion resistance or a relatively weak passivation film at the interface do not significantly diminish the corrosion resistance of TAD3D and 5A05Al. The corrosion resistance of the composite material initially decreases and then increases.

Resistance of Mycorrhizal Cinnamomum camphora Seedlings to Salt Spray Depends on K+ and P Uptake.

Salt spray is a major environmental issue in coastal areas. Cinnamomum camphora is an economically important tree species that grows in the coastal areas of southern China. Arbuscular mycorrhizal fungi (AMF) can alleviate the detrimental effects of abiotic stress on host plants. However, the mechanism by which AMF mitigates the adverse effects of salt spray on C. camphora remains unclear. A pot experiment was conducted in a greenhouse, where C. camphora seedlings were exposed to four AMF regimes (inoculation with sterilized fungi, with Glomus tortuosum, Funneliformis mosseae, either alone or in combination) and three salt spray regimes (applied with distilled water, 7, and 14 mg NaCl cm-2) in order to investigate the influence on root functional traits and plant growth. The results showed that higher salt spray significantly decreased the K+ uptake, K+/Na+ ratio, N/P ratio, total dry weight, and salinity tolerance of non-mycorrhizal plants by 37.9%, 71%, 27.4%, 12.7%, and 221.3%, respectively, when compared with control plants grown under non-salinity conditions. Mycorrhizal inoculation, particularly with a combination of G. tortuosum and F. mosseae, greatly improved the P uptake, total dry weight, and salinity tolerance of plants grown under higher salt spray conditions by 51.0%, 36.7%, and 130.9%, respectively, when compared with their counterparts. The results show that AMF can alleviate the detrimental effects of salt spray on C. camphora seedlings. Moreover, an enhanced uptake of K+ and P accounted for the resistance of the plants to salt spray. Therefore, pre-inoculation with a combination of G. tortuosum and F. mosseae to improve nutrient acquisition is a potential method of protecting C. camphora plants against salt spray stress in coastal areas.

Salt Spray Resistance of Roller-Compacted Concrete with Surface Coatings.

In order to evaluate the feasibility of surface coatings in improving the performance of RCC under salt spray conditions, sodium silicate (SS), isooctyl triethoxy silane (IOTS), and polyurea (PUA) were used as surface coatings to prepare four types of roller-compacted concrete (RCC): reference RCC, RCC-SS, RCC-IOTS, and RCC-PUA. A 5% sodium sulfate solution was used to simulate a corrosive marine environment with high temperatures, high humidity, and high concentrations of salt spray. This study focuses on investigating various properties, including water absorption, abrasion loss, compressive strength, dynamic elastic modulus, and impact resistance. Compared to the reference RCC, the 24 h water absorption of RCC-SS, RCC-IOTS, and RCC-PUA without salt spray exposure decreased by 22.8%, 77.2%, and 89.8%, respectively. After 300 cycles of salt spray, the abrasion loss of RCC-SS, RCC-IOTS, and RCC-PUA reduced by 0.3%, 4.4%, and 34.3%, respectively. Additionally, their compressive strengths increased by 3.8%, 0.89%, and 0.22%, and the total absorbed energy at fracture increased by 64.8%, 53.2%, and 50.1%, respectively. The results of the study may provide a reference for the selection of coating materials under conditions similar to those in this study.

Study on Blending Modification of Bisphenol A Epoxy.

Epoxy-resin-based composites in the field of current electrical materials often work in high temperature, high humidity or salt spray conditions. In order to improve the operation reliability of the composite insulator cross arm in a high temperature, high humidity and high salt spray environment, and analyze the aging mechanism and performance characteristics of resin, in this paper, wet heat aging and salt spray aging experiments were carried out on the blended resin system composed of bisphenol A type epoxy resin (E-51), aliphatic epoxy modified bisphenol A epoxy resin (2021P/E-51) and dimeric acid modified bisphenol A epoxy resin (EPD-172/E-51). Among them, 10 wt% and 20 wt% of 2021P blend resin and 10 wt% of EPD blend resin have superior thermo-mechanical properties. Under humid and hot conditions, the dielectric loss of 10 wt% EPD blend system before and after aging is 39.9% and 49.5% lower than that of pure E51 resin system, respectively. Under the condition of salt spray, the dielectric loss of 20 wt% and 10 wt% EPD blends decreased by 73.1% and 74.6% after aging. The leakage current of 10 wt% 2021P blend resin and 10 wt% EPD blend resin decreased by 7% and 3.8% before aging, respectively. After aging, they decreased by 3.7% and 2.2%, respectively. The bending strength of 2021P blend resin before and after aging reached 29.3 MPa and 26.6 MPa, respectively. The above three blending resin systems exhibit good electrical properties and good mechanical properties, their ageing resistance performance is strong and they are suitable as the matrix resin of compound cross arm mandrel material.

A Laboratory and Field Assessment of the Performance of Rebar Coatings.

Deteriorating concrete structures are repaired to restore their load-carrying capacity and enhance their appearance. As part of the repair procedure, the corroded reinforcing steel bars are cleaned by sandblasting, and a protective coating is applied to protect them from further corrosion. Generally, a zin-rich epoxy coating is used for this purpose. However, there have been concerns about the performance of this type of coating in protecting the steel due to the formation of galvanic corrosion, thus necessitating the need for developing a durable steel coating. In this study, the performance of two types of steel coatings, namely a zinc-rich epoxy and cement-based epoxy resin coating, was investigated. The performance of the selected coatings was evaluated by conducting both laboratory and field experiments. In the field studies, the concrete specimens were exposed to a marine exposure site for more than five years. The salt spray and accelerated reinforcement corrosion studies indicated that the performance of the cement-based epoxy coating was better than the zinc-rich epoxy coating. However, there was no visible difference between the performance of the investigated coatings in the reinforced concrete slab specimens placed in the field. It is suggested to use cement-based epoxy coatings as steel primers based on the field and laboratory data developed in this study.

Effect of Shot Peen Forming on Corrosion-Resistant of 2024 Aluminum Alloy in Salt Spray Environment.

The effect of shot peen forming on the corrosion-resistant of 2024 aluminum alloy in a salt spray environment was studied with an electrochemical workstation. The surface morphology and cross sectional morphology of the original and shot peen-formed sample were studied by a scanning electron microscope. After shot peen forming, the salt spray corrosion resistance of 2024 aluminum alloy was worsened (the corrosion rates of the original alloy and the shot peen-formed alloy were 0.10467 mg/(cm2·h) and 0.27333 mg/(cm2·h), respectively, when the salt spray corrosion time was 5 h). The radius of capacitive reactance arc of the sample subjected to shot peen forming was smaller than that of the original sample. When the salt spray corrosion time was 5 h, the doping density (NA) of the original alloy was 2.5128 × 10-13/cm3. After shot peen forming, the NA of the alloy increased to 15 × 10-13/cm3. For the shot peen-formed sample, pitting corrosion first occurred in the crater lap zone and became severe with salt spray time. The cross sectional morphology of both original and the shot peen-formed samples shows that severe intergranular corrosion occurred in the salt spray environment. However, for the original sample, the intergranular corrosion distribution was lamellar. For shot peen-formed sample, the intergranular corrosion distribution was network.

Study on the Aging Behavior of an Ultra-High Molecular Weight Polyethylene Fiber Barrier Net in a Marine Environment.

In the present work, the performance of ultra-high molecular weight polyethylene (UHMWPE) barrier nets in marine environments is investigated by Fourier transform infrared spectroscopy, thermogravimetry, scanning electron microscopy, and tensile experiments. The chemical, morphological, thermal stability, and strength changes after aging in salt spray, hygrothermal, and ultraviolet (UV) environments are characterized. An environmental spectrum is designed to simulate a real service environment and predict the service life of UHMWPE. The results show that UV energy can activate UHMWPE molecules and lead to chain breaking, which lowers the breaking strength more efficiently than salt spray. In a hygrothermal environment, the UHMPE fibers bond into clumps, which causes a slight increase in breaking strength after the initial rapid decrease with aging time. The acceleration ratio of the environmental spectrum increases with increasing aging time, which may be caused by the cross-linking and degradation of macromolecular chains in the material. The environmental spectrum given by this work can be used to evaluate performance and predict the service life of UHMWPE barrier nets in marine environments.

Analysis of Erosion Characteristics and Erosion Mechanism of Polypropylene Fiber Tailings Recycled Concrete in Salt Spray Environment.

Economic development and infrastructure improvement will inevitably lead to the accumulation of construction waste and tailings, which has not only a huge impact on the environment but is also a waste of resources. Recycling these resources and making green concrete is an effective way to solve these problems. In this study, the salt spray erosion characteristics and erosion mechanism of tailings recycled concrete (TRC) with polypropylene fibers were studied through macro and micro methods. The results showed that its compressive strength and splitting tensile strength increased at first and then decreased, with the optimum content of 0.6-0.9%, and the strength increase coefficient reached its maximum value at the erosion period being 14 d to 28 d. Under the same erosion cycle, when the fiber content was low (≤0.6-0.9%), the erosion depth hardly fluctuated. While the fiber content changed from 0.6% to 1.2%, the erosion depth and curing ability (erosion for 90 days) increased by 16.29% and 11.20%, which implied that its erosion resistance decreased sharply. Through SEM microscopic analysis, it could be observed that when the fiber content was low, the matrix structure and porosity had little change; while the fiber content was excessive, the porosity increased greatly. The longer the erosion period was, the greater the cumulative expansion of salt crystals was, and the larger the porosity was, whose results were in good agreement with the experimental results. This research provides a significant theoretical basis for the application of TRC in engineering.

Insight of Salt Spray Corrosion on Mechanical Properties of TA1-Al5052 Self-Piercing Riveted Joint.

Self-piercing riveted (SPR) joints in automobiles inevitably suffer from corrosion damage and performance reduction. In this work, the influence of salt spray corrosion on the mechanical properties of TA1-Al5052 alloy SPR joints was studied. The TA1-5052 SPR joints were prepared and salt spray tests were carried out for different durations. The static and fatigue strengths of the joints after salt spray corrosion were tested to analyze the effect of salt spray duration on the performance of the joints. The results show that the joints' static strength and fatigue strength decrease with prolonged salt spray time. The salt spray duration affects the joint's tensile failure mode. The tensile failure without corrosion and with a short salt spray time is the fracture failure of the lower aluminum sheet, and the tensile failure of the joints after a long time of salt spray corrosion is the failure of the rivets. The fatigue failure form of the SPR joint is the formation of fatigue cracks in the lower aluminum sheet, and salt spray time has little effect on the fatigue failure form. Salt spray corrosion can promote the initiation and propagation of fatigue cracks. The fatigue crack initiation area is located at the boundary between the lower aluminum sheet and the rivet leg. The initiation of cracks originates from the wear zones among the sheet metal, rivets, and salt spray particles.

Preparation of Cemented Carbide and Study of Copper-Accelerated Salt Spray Corrosion and Erosion Behavior.

(1) Mud pulser carbide rotors, as a core component of ground communication in crude oil exploration, are often subjected to mud erosion and acid corrosion, resulting in pitting pits on the surface, which affects the accuracy. The purpose of this study was to investigate the acid corrosion and erosion behavior of cemented carbide materials and provide a reference for the wider application of cemented carbide materials in the petrochemical industry. (2) Experimental samples of tungsten-cobalt carbide were sintered at a low pressure by powder metallurgy. The petrochemical application environment was simulated by accelerated salt spray corrosion and solid slurry erosion with the aid of acidic copper, and the experimental phenomena were analyzed by SEM (scanning electron microscope), EDS (Energy Dispersive Spectroscopy), and XRD (X-ray diffraction). (3) The experimental results show that the coercivity of the pitted cobalt-cemented tungsten carbide prepared in this study was 17.89 KA/m, and the magnetic saturation strength was 14.42 G·cm3/g. The corrosion rate was the fastest during the acidic copper acceleration experiments from 4 h to 16 h, and the corrosion products of WCo3 and Co3O4 were generated on the corrosion surface. The maximum erosion rate of 0.00104 in the erosion experiment corresponds to a corrosion sample with a corrosion time of 36 h. (4) Therefore, the coercive magnetic force and magnetic saturation strength could be derived from the prepared carbide hard phase grains and carbon content in the appropriate range. The corrosion product in the corrosion process slowed the corrosion rate, and a large amount of cobalt and a small amount of tungsten was lost by oxidation during the corrosion process. The corrosion time had the greatest effect on the erosion performance of the carbide, and the long corrosion time led to surface sparseness, which reduced the erosion resistance.

Research on the Corrosion Behavior of Q235 Pipeline Steel in an Atmospheric Environment through Experiment.

Low-carbon steel pipelines are frequently used as transport pipelines for various media. As the pipeline transport industry continues to develop in extreme directions, such as high efficiency, long life, and large pipe diameters, the issue of pipeline reliability is becoming increasingly prominent. This study selected Q235 steel, a typical material for low-carbon steel pipelines, as the research object. In accordance with the pipeline service environment and the accelerated corrosion environment test spectrum, cyclic salt spray accelerated corrosion tests that simulated the effects of the marine atmosphere were designed and implemented. Corrosion properties, such as corrosion weight loss, morphology, and product composition of samples with different cycles, were characterized through appearance inspection, scanning electron microscopy analysis, and energy spectrum analysis. The corrosion behavior and mechanism of Q235 low-carbon steel in the enhanced corrosion environment were studied, and the corrosion weight loss kinetics of Q235 steel was verified to conform to the power function law. During the corrosion process, the passivation film on the surface of the low-carbon steel and the dense and stable α-FeOOH layer formed after the passivation film was peeled off played a role in corrosion resistance. The passivation effect, service life, and service limit of Q235 steel were studied and determined, and an evaluation model for quick evaluation of the corrosion life of Q235 low-carbon steel was established. This work provides technical support to improve the life and reliability of low-carbon steel pipelines. It also offers a theoretical basis for further research on the similitude and relevance of cyclic salt spray accelerated corrosion testing.

Comparing the Corrosion Resistance of 5083 Al and Al2O33D/5083 Al Composite in a Chloride Environment.

In this study, an Al2O33D/5083 Al composite was fabricated by infiltrating a molten 5083 Al alloy into a three-dimensional alumina reticulated porosity ceramics skeleton preform (Al2O33D) using a pressureless infiltration method. The corrosion resistance of 5083 Al alloy and Al2O33D/5083 Al in NaCl solution were compared via electrochemical impedance spectroscopy (EIS), dynamic polarization potential (PDP), and neutral salt spray (NSS) tests. The microstructure of the two materials were investigated by 3D X-ray microscope and scanning electron microscopy aiming at understanding the corrosion mechanisms. Results show that an Al2O33D/5083 Al composite consists of interpenetrating structure of 3D-continuous matrices of continuous networks 5083 Al alloy and Al2O33D phase. A large area of strong interfaces of 5083 Al and Al2O33D exist in the Al2O33D/5083 Al composite. The corrosion development process can be divided into the initial period, the development period, and the stability period. Al2O33D used as reinforcement in Al2O33D/5083 Al composite improves the corrosion resistance of Al2O33D/5083 Al composite via electrochemistry tests. Thus, the corrosion resistance of Al2O33D/5083 Al is higher than that of 5083 Al alloy. The NSS test results indicate that the corrosion resistance of Al2O33D/5083 Al was lower than that of 5083 Al alloy during the initial period, higher than that of 5083 Al alloy during the development period, and there was no obvious difference in corrosion resistance during the stability period. It is considered that the elements in 5083 Al alloy infiltrated into the Al2O33D/5083 Al composite are segregated, and the uniform distribution of the segregated elements leads to galvanic corrosion during the corrosion initial period. The perfect combination of interfaces of Al2O33D and the 5083 Al alloy matrix promotes excellent corrosion resistance during the stability period.

Effect of Temperature on the Corrosion Behavior and Corrosion Resistance of Copper-Aluminum Laminated Composite Plate.

In this paper, the effect of temperature on the corrosion behavior and corrosion resistance of the copper-aluminum laminated composite plates were investigated by salt-spray corrosion, potential polarization curve and electrochemical impedance spectroscopy. Moreover, the microstructure of the copper-aluminum laminated composite plate after salt-spray corrosion was observed by scanning electron microscope, and X-ray photoelectron spectroscopy was used to study the composition of corrosion product. The results revealed that the corrosion products of the copper-aluminum laminated composite plate were Al2O3 and AlOOH. Due to the galvanic corrosion of the copper-aluminum laminated composite plate, the cathode underwent oxygen absorption corrosion during the corrosion process; therefore, the presence of moisture and the amount of dissolved oxygen in the corrosive environment had a great influence on the corrosion process. The increasing temperature would evaporate a large amount of moisture, resulting in the corrosion product-aluminum oxide dehydrated and covered the surface of the material in the process of salt-spray corrosion, which played a role in protecting the material. Therefore, the corrosion resistance of the copper-aluminum laminated composite plate first decreased and then increased. In the salt-spray corrosion environment, the corrosion resistance of the copper-aluminum laminated composite plate reached the lowest at 45 °C, and its corrosion rate was the fastest, at 0.728 g/m2·h. The electrochemical corrosion occurred in the solution, and the impact was small; however, in addition to the protective corrosion products, the ion mobility in the solution also had a certain influence on the corrosion rate, and the ionic activity increased with the increase of temperature. Therefore, the corrosion resistance of the copper-aluminum laminated composite plate gradually decreased as the temperature increased, and its corrosion resistance was the worst at 50 °C.

[Aerosol salt damage is the main problem of landscaping in the coastal areas of southern China]. / 盐雾危害是南方滨海地区园林绿化的主要困难.

Both the growth and survival of landscape plants are difficult due to the harsh natural conditions in coastal areas of southern China. Many plants suffer from symptoms of salt damage. Different from the damages by salt in the soil, the symptoms of windblown salt are damage to young shoots and leaves. Plants at the windward side are damaged more than the leeward side. These cha-racteristics imply that the damage is due to salt in aerosols instead of salt in the soil. To test this hypothesis, we measured plant growth, soil and climate factors in 24 frontline coastal counties and cities of China. The results showed that the first-line coastal plants showed strong symptoms of salt damage, especially in the Taiwan Strait area (85.4% belonged to desalinized soil), and that the damage level was highly correlated with wind speed. Our results confirmed that aerosol salt is the major cause of plant damage in the coastal areas of southern China. We constructed the first distribution map of salt damage along frontline coastal regions of southern China and proposed methods for diagnosing aerosol salt damage. Selecting and configuring aerosol salt-tolerant plants, greening engineering measures, and follow-up maintenance were suggested for improving the overall effect and level of landscaping in the coastal areas of southern China.