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Silica antireflective coatings by the base catalyzed sol–gel process show poor mechanical property. In this study, the base-catalyzed sol was modified by acid-catalyzed polysiloxane and nano-TiO 2 sol. The single layer antireflective films were prepared using spray coating technology, the effects of transmission speed on the optical performance of the films were studied. The results show that the films derived from the modified sol have an excellent weather resistance. Its degradation of transmittance after damp-heat test is only 0.23%. The maximum transmittance of the antireflective solar glass with single layer coating is about 95.02% at 565 nm wavelength, which is about 3.36% higher than the substrate glass. The adhesion of the film is 5B and the pencil hardness is equal or higher than 3H. High transmittance, good mechanical properties and excellent durability make the films be suited to solar glass.

Co/SiO 2 composite particles were prepared by fabricating SiO 2 shell on the surfaces of dendritic Co particles. The effects of SiO 2 shell and annealing treatment on microstructure evolution and performance improvement of Co/SiO 2 composite particles were investigated. It was found that, Co/SiO 2 composite particles exhibited weather resistance when exposed to high temperature air or diluted hydrochloric acid. Coatings containing Co/SiO 2 composite particles as fillers presented high electromagnetic wave absorbing efficiency and thin matching thickness. The weather resistance and the electromagnetic wave absorbing performance were further improved after an annealing treatment.

When the facade of a 50-year-old edifice in New York City began to show its age, an exhaustive investigation explored two alternative schemes for repairing the white glazed brick exterior. Ultimately, the solution agreed upon by the design team and the owner is an unconventional cavity wall design—specifically, a terra-cotta rain screen—that will greatly improve the building’s weather resistance and energy performance while lending contemporary aesthetic appeal.

The physicochemical properties of two newly developed dirt-resistant cool white coatings were systematically measured in light of the relevant standard testing methods, and the influences of dirt accumulation and washing on the long-term cooling performance of cool coatings were investigated and discussed. Both cool white coatings owe their outstanding physicochemical properties to the optimized formulations, high glass transition temperature and minimum film formation temperature of selected aqueous self-curing acrylic emulsions. The high solid content was also influential. Dirt accumulation leads to a decline in the cooling performance of coatings, which may be almost fully restored by simply washing the coatings with a mild soap solution.

Through sol-gel and dip-coating processes, commercial polyurethane sponge modified by polysiloxane was fabricated under low temperature (60 °C) and atmosphere. The contact angle of the obtained polysiloxane/polyurethane sponge is 145 ± 5°. Hence, the polysiloxane/polyurethane sponge could float on water and selectively absorb organics from the surface of the water, indicating simultaneous properties of hydrophobicity and oleophilicity. The absorbent maximum value is 50–150 times of its own weight. The polysiloxane/polyurethane sponge exhibited excellent recyclability, which could be reused by squeezing the sponge due to its high mechanical stability and flexibility. Thermogravimetry-differential thermal analysis test indicated that the polysiloxane/polyurethane sponge exhibited good thermal stability and the stable contact angle of samples tested under increasing temperature indicated its good weather resistance. Due to the commercial property of polyurethane sponge and easy-handling of polysiloxane, the polysiloxane/polyurethane sponge can be easily scaled up to recover a large-area oil spill in water and further work based on the designed equipment has been under consideration.

Objectives Hair sprays apply fixative ingredients to provide hold to a hair style as well as weather resistance and optical properties such as shine. Generally, sprays distribute fine particles containing polymeric ingredients to form a thin film on the surface of hair. Different hair types require different strengths of the formed deposit on the hair surface. The present study shows how sprays also alter the visibility of the hair color by altering the surface topology of the hair fibers. Methods Hyperspectral imaging is used to map spectral characteristics of hair on mannequins and panelists over the curvature of heads. Spectral and spatial characteristics are measured before and after hair spray applications. The hair surface is imaged by SEM to visualize the degree of cuticle coverage. Finally, the perception of hair color was evaluated on red colored mannequins by consumer questionnaire. Results Hair sprays deposit different degrees of fixatives which lead to a progressive leveling of the cuticle natural tilt angle with respect to the fiber axis. As a result, shine is progressively shifting towards the region of hair color visibility and decreases the perceived color of hair seen by consumers. Lighter sprays show thinner film formation on the hair surface and less of a shine shift than strong hold hair sprays. Conclusions Hair sprays are generally employed for hair style hold and weather resistance and considered without effect on hair color. Our approach shows that spray deposited films can affect color perception by altering the microstructure of the hair surface. Thin films deposited on the hair fiber surface can partially fill gaps between cuticles which reduces the cuticle natural angle. This partial erasure results in a angle shift of the shine regions towards the angle of internal reflection, thus decreasing the perceived hair color regions as experienced by a group of consumers. This article is protected by copyright. All rights reserved.

Building leakage is a chronic and stubborn disease to influence the quality of building engineering. The traditional waterproof coiled material such as asphalt has properties of poor weather resistance, easy to crack and large pollution. GT is a kind of green building material with superior performance. GT materials used in building waterproof can fundamentally solve the problem of waterproofing, impermeability and plugging in construction. In this article, the author discuss performance characteristics, construction technical measures and quality testing standards of GT paint, analysis the technical points of GT waterproof paint applied in construction engineering.

PurposeThe purpose of this paper is to formulate two component polyurethane coatings based on acrylic polyol, to study the effects of variable nanosilica loadings in these coatings on different morphological, optical, mechanical, corrosion resistance and weather resistance properties and to study the intercalation of acrylic polyol molecules into nanosilica crystals by XRD technique.Design/methodology/approachTwo component polyurethane coatings were synthesised using acrylic polyol and isocyanate HDI. The nanosilica was incorporated in polyurethane formulation at the weight ratios of 1%, 3% and 5% based on total weight of polyol and isocyanate. The performance of nanocoatings was compared for variable loads of nanosilica for different properties such as morphological, optical, mechanical, corrosion resistance, weather resistance and were studied for intercalation of acrylic polyol into nanosilica crystals by XRD technique.FindingsImprovement in the properties of polyurethane coatings is achieved with the incorporation of nanosilica. The improvement is the result of inherently high properties of inorganic nanosilica. Tensile strength, scratch hardness, abrasion resistance, corrosion and weathering resistance show significant improvement in performance with the incorporation of nanosilica. Properties are found to deteriorate beyond a certain loading of nanosilica; hence it is important to optimise loading level. The optimal range for high performance was found to be in the range of 1% to 3%. The improvement was a result of synergistic behaviour and good interfacial interaction between polyurethane and nanosilica at optimal levels.Research limitations/implicationsThe method used for incorporation of nanosilica into polyurethane was direct incorporation method. The other method of incorporation, i.e. in situ addition and its effect on properties can also be studied.Practical implicationsWith the addition of optimal loading level of nanosilica to polyurethane coatings, properties can be enhanced up to the mark. The addition is relatively easy and cost effective.Originality/valueThe paper proves the significance of incorporation of nanosilica on original properties of polyurethane coatings and widens the area of applications of two component polyurethane coatings from acrylic polyol by strengthening them in their properties. The coatings can be applicable in high performance topcoats especially for automotive topcoats.

Weather resistance properties of the sintered clay body (SCB) mixed with various content of sewage sludge incineration ash (SSIA) has been investigated. The result indicates that the water absorption ratio of SCB mixed with SSIA increased linearly with the increase of the content of SSIA, while the saturation coefficient remained constant. After the freeze-thaw cycles, the SCB body mixed with SSIA showed a stable and smooth appearance. From the SEM results, the internal porosity and pore size of SCB raised significantly with the increase of content of SSIA.

The conservation of weathered historic sandstone with apatite was studied. Based on the growth mechanism of bone, calcium and phosphorus were introduced into weathered sandstone and then mineralized at room temperature. The conservation efficiency was investigated by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), selected area electron diffraction (SAED), X-ray diffraction (XRD), and compressive strength, capillary water uptake, water vapor permeability and weather resistance tests. The SEM, EDX, TEM, SAED and XRD results showed that the produced hydroxyapatite could reunite the weathered stone blocks and provide sufficient reinforcement to hold them together. The results of the various tests indicated that the compressive strength and weather resistance of the treated samples was improved significantly. In addition, because of the porous nature of apatite, the water vapor permeability of the treated stone was not affected and its breathability was maintained.

New naturally occurring mineral based pigment of general formula Hg2S have been processed and characterized for its application in surface coating. Various analytical protocol like XRD, FT-IR, SEM and CIE 1976 colour coordinate system have been performed for complete analysis of pigment. Characterizations using XRD, and CIE 1976 colour coordinate assessment reveal the formation of pigments displaying colours ranging from brick-red to dark-brown. The typical designed pigment samples have been evaluated for their mass tone/hiding power, tinting strength and weather resistance by coating on an MS steel panel. Optical, Chemical, Mechanical and performance properties of coating have been evaluated for its application. The results demonstrated that the dark-brown pigment obtained in the present study was found to be an interesting alternative to the existing classical toxic inorganic red pigments for surface coating applications.

The traditional waterproof membrane on roof such as asphalt membrane, SBS and APP modified bitumen membrane has poor weather resistance and poor durability. So, leakage phenomenon often appears. While GT waterproof material, each property is superior, the construction is simple and efficient, which applied to waterproof of building roof has broad prospects, can thoroughly cure roof leakage problems. According to the properties, characteristics and applicability of GT material, analysis its technology points of base treatment and construction measures applied in roof waterproof.

In this study, carbon fiber/ polypropylene (PP) complex braiding yarn, with its different breaking strength, was prepared. It was designed by braiding polypropylene (PP) wrapped yarn and carbon fiber core yarn using eight and sixteen spindles braiding machines, with change of take-up gear number. Environmental factors, such as pH, temperature and time, were also changed to produce geo-grids with high strength, high modulus and better weather resistance. In order to make stable structure for complex braiding yarn, the heat treatment was also considered. Finally, geo-grids braiding by optimal treatment parameters were cut into single rib and junction specimens for tensile test.

Two camouflage paints were developed respectively on the surface of concrete and metal surface for getting high weather resistance. Different materials and their ratios especially those used in anti-aging agents, pigments and fillers were studied. Results indicated the prepared compound formula could significantly improve the properties of camouflage paints. The useful lives of products were extended and could meet the requirement of military.

High strength and performance steel with high strength, good ductility and welding property, weather resistance, material-saving and so on, have been popularized and used in high-rise and large-span buildings, as well as roads and bridges. Researchers are suggested to put forth new structural design theories and develop new structural steel and systems to meet the higher and higher requirements towards the properties of structural steel raised by the increasingly diverse, complex, and novel modern building structures. Through discussing the current situation about the studies on and the employment of high strength and performance steel at home and abroad and analyzing some existing problems of the current theories and design methods on steel structure buildings, the paper aims at providing references and conducts for later relevant studies.

Es wurde die Witterungsbestandigkeit von Fichtenholz und Buchen holz nach Beschichtung mit verschiedenen nanoskaligen Hydrophobierungsmitteln und vergleichsweise dazu mit einem ublichen Lack getestet. Die Impragnierung des Holzes erfolgte uber Streich- oder Druckimpragnierung. Erfasst wurden Anderungen der Farbkennwerte, der Benetzungswinkel, der Holzfeuchte sowie der visuelle Gesamteindruck. Bei allen Materialien und Beschichtungs arten trat bereits nach kurzer Zeit eine Vergrauung auf. Diese war beim Standardlack am geringsten. Diese Tendenz spiegeln auch die Farbmessungen wieder. Der Benetzungsrandwinkel reduzierte sich zunehmend, das zeigt, dass der Hydrophobierungseffekt nach lasst. Beim Standardlack war der Effekt deutlich geringer ausgepragt. Insgesamt zeigt sich, dass es weder mit Streich- noch mit Druckimpragnierung gelang, das Impragnierungsmittel ausreichend tief in das Holz einzubringen und zu fixieren. Dies deckt sich mit den Ergebnissen der Flussigkeitsaufnahmekoeffizienten, uber die in vorangegangenen Arbeiten berichtet wurde. Investigation regarding the behaviour of wood impregnated with nano-particles and exposed to the open weather. The weather resistance of Norway spruce and beech wood has been tested following coating with various nano-scale hydrophobising compounds, and has been compared with reference samples that were coated with a standard varnish. The impregnation of the timber was carried out by brush coating or a pressure process. The test results focused on changes in colorimetric values, wetting angle, timber moisture and the overall appearance. All materials and types of coating were subject to a greying of colour after a short while. The standard varnish showed the least discoloration. This tendency was also reflected in the colorimetric measurements. The wetting edge angle increasingly reduced, indicating that the hydrophobising effect was also reducing. With the standard varnish, this effect was clearly less pronounced. Overall, the tests showed that it had not been possible to inject the timber sufficiently deeply with the impregnation compound, and fix it, with either the brush or pressure impregnation method. This confirms the findings obtained in fluid retention co-efficient tests which were reported in previous articles.

Polyurea coatings are known to provide high hardness, stable color, excellent weather durability and good scratch resistance. Being cured, the coatings can also express heat resistance up to 150 oC, good resistance to acids, oils, as well as other chemicals, high flexibility and strain, excellent adhesion to various substrate materials such as concrete, steel, ceramic, glass and others. In this paper, a polyurea coating has been developed on basis of polyaspartic acid esters and polyisocyanate curing agent, using 3 % nanoclay additive. The physical, mechanical, and chemical properties of the coatings were examined by current technical specifications. The results for developed coating were recorded as follow: 76 in.lb impact strength, 7.5 mm elongation, and 0.7 relative hardness; no blistering was observed after 30 days of immersion in 5 % HCl and 5 % NaOH solutions. Weather resistance of the coatings was also evaluated with full absence of peeling, blistering and high gloss retention after 500 h accelerated UV testing.

The main problem of salt production in Indonesia is low productivity and quality because the technology used commonly by Indonesian salt farmers is traditional method. This research aims to increase production of salt by using the prism greenhouse method. The prism greenhouse method is a salt production system with a combination of several salt production technologies, including geomembrane, threaded filter, and prism greenhouse technology. This research method used descriptive method. The results of this study were the productivity increased threefold, and the quality of salt produced also increased in terms of the content of NaCl from 85% to 95%. In addition, salt production with the prism greenhouse method has several advantages, such as faster harvest time, weather resistance, easy to use, and higher profit than traditional methods.

The weather resistance of 10CuPRE、10CuP and Q235 steels were studied by dry-wet cyclic immersion test. The corrosion resistance mechanism of rare earth Cu-containing weathering steel was studied through electrochemical polarization test, scanning electron microscope(SEM) and X ray diffraction(XRD). The results show the small and spherical rare earth oxysulfides replace the elongated MnS inclusions in the rare earth weathering steel. Less and fewer rare earth oxysulfides heavily decrease pitting susceptibility and rate of pit propagation. So the electrochemical corrosion of microarea in the steel matrix is weakened after rare earth was added in the Cu-containing weathering steel. The inner rust layer of rare earth weathering steel is more compact and uniform than that of weathering steel without rare earth. The main corrosion product on the rare earth weathering steel is α-FeOOH. The formation of the steady corrosion product is promoted by rare earth, which result in that the protective property of the inner rust layer on weathering steels is enhanced. As a result, the corrosion resistance of Cu-containing weathering steel is improved by rare earth elements.

The design technology to be developed in this study is technology related to the metal panel corner processing method of very high value-added, interior and exterior cladding material, in the architecture. This study is aimed at designing a Bending Die System that enables metal panel corner processing for the first time in Korea, by improving corrosion resistance (durability), weather resistance and elegances (design) for the connecting part of right angle cornering, where most serious problems occur in using metal steel plates of 2.5mm or thicker. This is used as a kind of metal ball and as architectural interior and exterior cladding material.

The design technology to be developed in this study is technology related to the metal panel comer processing method of very high value-added, interior and exterior cladding material, in the architecture. This study is aimed at designing a Bending Die System that enables metal panel comer processing for the first time in Korea, by improving corrosion resistance (durability), weather resistance and elegances (design) for the connecting part of right angle cornering, where most serious problems occur in using metal steel plates of 2.5mm or thicker. This is used as a kind of metal ball and as architectural interior and exterior cladding material.

Preparation and properties of wood/plastic composite (WPC) with high content of wood filler around 80% are reported focusing at: effects of high filler content, preparation of all bio-based composite by using poly(lactic acid) (PLA) as plastic material and cellulose esters as compatibilizer, and method for improving weather resistance of wood/PP composite. Addition of about 2% of cellulose esters of C4-C6 aliphatic carboxylic acids was effective for improving the bending strength of high wood content WPC of PLA by slowing down the crystallization rate of plastic. For improving weather resistance of wood/PP composite, top-coating was found most effective.

Since the mid sixties Cor-Ten® steel became one of the most famous materials for outdoor sculptures until today. This material was used by many artists because of its good weather resistance. Due to not always suitable ranges of application many significant problems in the field of conservation appeared. These were surveyed in a project of the study programme ‘Object Conservation’ at the State Academy of Art and Design Stuttgart with special focus on the material and its protective rust layers, the premises for its protection, different cases of significant damage and their causes, the potential of preventive conservation and practised interventive methods. Although it seems to be in some way a contradiction in itself to coat a weathering steel, this has often been done in hands-on conservation to overcome corrosion problems. Therefore different coating materials already in use for outdoor metal sculptures were tested on Cor-Ten coupons in the framework of the CONSIST project in the Deutsches Bergbau-Museum Bochum (DBM). Cor-Ten B samples were covered with different coating materials such as: microcrystalline waxes, waxes used in technical corrosion protection, an acrylic resin and a polyurethane resin. The sheets were then weathered for 2 months in a climate chamber with a relative high humidity (but also drying cycles) and a climate chamber with a periodic changing relative high rate of SO2 gas and humidity using standard protocols developed at DBM in earlier projects. The effectiveness of the protective function of each coating materials is compared, consequences for practical applications discussed.

A new surface treatment technology for the aluminum alloys that exhibits not only high corrosion and weather resistance but also good mirror luster has been developed. By performing electrolytic permeation, the improved corrosion resistance and weather resistance while maintaining a high mirror luster was achieved for an aluminum alloy A2014-T6. The high strength aluminum alloys featuring high corrosion and weather resistance have been available for industrial products. Then the claim number of the products by A2014 T6 aluminum alloy has been reduced sharply to almost zero level in comparison with a past. A few applications and the development of the processing in industrial scale in A2014 T6 aluminum alloy will be presented.

Waterborne alkyd and acrylic resins can be modified with silicone intermediates to improve their weather resistance in paints for exterior applications. The alkyds are modified through copolymerization before dispersion in water, using formulations and process conditions that minimize the tendency to gel. Acrylic latexes can be post treated with selected silicone intermediates at ambient temperature to give hybrid coating binders. In both cases, the gloss retention and chalking resistance of paint films are greatly increased.

This paper presents the research of the impact of acidic precipitation on painted building facades’ rendering. Four typical kinds of the building facade paints have been chosen. The moisturing–drying cycling laboratory tests simulating acidic atmospheric precipitations and also natural weathering in the field have been carried out. A significant effect on the painted render during moisturing by acidic solutions with the successive drying out has been found, and this ought to be taken into account when setting up the conditions of artificial aging tests in order to predict and compare the weather resistance of painted renderings. The research has shown that the growth of the intensity of initial water absorption and deterioration rates is significantly influenced by the presence of acid depositions on a painted surface of rendering during both artificial laboratory and natural weathering tests. The results of the tests have discovered that acidic depositions are one of several very important weathering factors that should be taken into account.

The ECDIS (electronic chart display and information system) is a new technology of modern navigation, sailing aims to ensure navigation safety, and improve work efficiency. AIS (automatic identification system) is a kind of can transmit large amount of information, obstacle, weather resistance, with ship shore - ship between information networking ability and close target indication of maritime communication system. And ship collision avoidance system is an important research subject in modern navigation technology, it in the prevention of ship collision accidents, ensure the safety of ship navigation plays a very important role. This paper developed based on ECDIS and AIS ship collision avoidance warning system. The simulation shows that the system is feasible.

The research analyzed the application status of Pu aluminum composite panels, summarizes research status of thermal insulation material in the domestic and foreign, especially the related properties of materials, such as combustion, heat insulation, weather resistance; related development and external wall insulation decorative integration materials present has done some introduction. The paper use aluminum alloy decorative board with thermal insulation and integrated decoration produced by the factory, combined with a keel and anchor bolt connection, is directly fixed on the outer wall of a building, can realize the building exterior wall thermal insulation decorative function, the system also has a good waterproof, fireproof performance, construction process comprehensively can use dry homework.

A new series of natural lacquer/polyurethane (LPU) blended films were synthesized. The new lacquer/polyurethane films have very good visual color and detected gloss, fast drying time, strong weather resistance, especially against UV light and water, and a better pencil lead hardness (8H). The gel ratio increases with drying time and becomes stable after 6 months (more than 99%). The surface glass transition temperature ( T g s) obtained from a rigid-body pendulum physical properties testing (RPT) instrument showed that the new LPU films dried for 6 months have higher T g s than polyurethane (PU) films in the following order: LPU 100 > LPU 90 > LPU 80 > LPU 70 > LPU 60 > LPU 50 > PU. Differential scanning calorimeter (DSC) results showed the same tendency as T g but without a great gap in the LPU series except for polyurethane. Thermogravimetric analysis (TGA) showed that when the ratio of natural lacquer is more than 50%, the 50% weight loss temperatures increase about 100 °C. In addition, the reaction between lacquer and polyurethane is discussed based on the IR and NMR measurements.

Searching for an economical and effective sand-fixing material and technology is of great importance in Northwest China. This paper described the use of a semihydrated gypsum-(CaSO4 ⋅ 1/2H2O-)based composite as a sand-fixing material. Its morphology and composition were characterized by SEM, and its water resistance, freezing–thawing resistance and wind erosion resistance were tested in the field. The results indicated that semihydrated gypsum-(CaSO4 ⋅ 1/2H2O-)based sand-fixing composite has good water resistance and water-holding capacity. Its strength is maintained at 1.42 MPa after 50 freezing and thawing cycles, and its wind erosion increases with increasing wind speed and slope. Its compressive strength starts to decrease after nine months of field tests with no change in appearance, but it still satisfies the requirements of fixation technology. This sand-fixing material should have wide application owing to its good weather resistance.

Water-borne paints first appeared on the market of building materials in Belarus and Lithuania in the early 1990s. These paints had to compete with solvent-based products traditionally used for mineral surfaces. Water-borne paints were able to quickly gain popularity despite the initial doubts of consumers and higher price. This was due to a number of advantages of water-borne paints such as high weather resistance, light fastness, low water absorption, resistance to chalking, high adhesion. Typical formulations of water-borne paints developed and implemented in the production by the authors were analyzed in the article. Pure acrylic and styrene-acrylic polymer dispersions were used as film formers, talcum and marble powder were used as fillers. Monitoring of different types of painted surfaces conducted by the authors showed not only the advantages but some disadvantages of the paints. These include delamination of coatings due to their incompatibility with the base, discoloration due to the use of organic pigments with low stability etc. Directive 2004/42/CE of the European Parliament and of the council of 21 April 2004 on the limitation of emissions of volatile organic compounds (VOC) due to the use of organic solvents in certain paints and varnishes and vehicle refinishing products (in Lithuania) and Technical Regulations of the Customs Union "On the security of paints and varnishes" (in Belarus) show that water-borne paints with low VOC will tend to dominate in market.

This paper is devoted to the study of bitumen compatibility with mixed thermoplastic rubber designed for its modification which is three polymer mixture. Unlike most popular bitumen modifiers based on butadiene and styrene copolymers having unsaturated main chain, the proposed polymer is composed of components with saturated hydrocarbon main chain. Thus, the increased weather resistance is provided for the products and designs based on modified bitumen. The solubility of mixed thermoplastic rubber and its components separately is studied. © Makarov et al.

Previously, we reported that the amount or activity of the root relative to shoot was an important fact or relating to the sterility caused by cool temperatures. To elucidate the causal relationship between the relative amount or activity of roots and the cool-weather resistance, we modified the amount or activity or roots experimentally. When about 75% of roots or all tillers were cut off at the pollen mother cell formation stage just before the young microspore stage, there was no reduction in the fertility of the plants cooled at the young microspore stage. Howecver, the fertility of the cooled plants was significantly reduced by the root cutting at the primary rachis branch differentiation stage, and also by the treatment or roots with a respiratory in hibitor or addition of glucose to the pots, which was expected to reduce the root activity through a reduction of soil. These results indicated that there was a causal relationship between the amount or activity of roots and the cool-weather resistance. In addition, the cool-weather recsistance was reduced by the root cutting at the primary rachis branch differentiation stage but not by similar treatment given just before the critical(cool-weather sensitive) stage. These facts suggest that the root does not affect the cool-weather resistance at the critical stage, but affccts it at a stage earlier than the critical stage, for example, through the effect on the process of pollen formation.

Journals written by a farmer family in the village ofNorÐoyri, Faeroe Islands have made it possible to obtain detailed information on important aspects of the operation of a Faeroesefarm over a long time span. This article, covering the period 1813–1892, concentrates on the analysis of plant production, i.e. haymaking, grain and potato growing. While haymaking for winter fodder for cows was relatively stable, a new crop, potatoes, first planted in 1823, gradually took over the role of grain. This happened, it is concluded, because of its weather resistance, stability and more flexible harvesting period—seen in relation to grain. Furthermore, the journals contain information or proxy data that admits statements on climatic variation. It is shown that there have been three periods with good climatic conditions separated by three worse periods, within the time span considered.

Titanium dioxide, TiO2, being a prime pigment, has been used extensively in the paint industry. The growing demand and the increasing cost of TiO2 has driven the attention of paint technologists to search for other alternatives. There has been continuous effort to replace part of the TiO2 with a fine particle size extenders in paint formulations. A detailed study has been undertaken to replace TiO2 pigment by various percentages of calcined clays in two latex paint formulations. Properties such as thixotropy, hiding power, light fastness, film brightness, scrub resistance, and weather resistance have been determined to establish the optimum use of calcined clays in the paint formulation. Thixotropy, one of the important properties of latex paints, has been studied with the help of thixotropic loop area method. The viscosity data has also been analyzed by Casson's equation. It has been found that the calcined clays can replace up to 20% TiO2 in paint formulations without having any adverse effect on their properties. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1029 -1036, 2000

The difference in the number of pollen grains may be the primary factor determining the resistance to cool weather at the young microspore stage in rice (Oryza sativa L.) cultivars. To confirm this hypothesis, we compared the number of pollen grains among the cultivars or lines with various cool-weather resistance. The cultivars or lines used in the experiments were mainly released or grown in the Tohoku district (the northern part of the mainland of Japan). The number of pollen grains showed high correlation with the degree of cool-weather resistance, but considerably varied with the cultivar or line, even in the group having the same cool-weather resistance. Each group with different cool-weather resistance was divided into two subgroups, implying the existence of another genetic factor determining the resistance. The number of pollen grains in the plants cooled at the young microspore stage showed higher correlation with the degree of the cool-weather resistance than that in the control plants without exposure to low temperature. The correlation between the pollen number and spikelet sterility was also analyzed using the data of Satake and Shibata (1992, Jpn. J. Crop Sci. 61 :454–462), who primarily used the cultivars in Hokkaido (the northernmost island of Japan). The results were basically the same as those obtained in the present experiments. These results confirmed the hypothesis that the variation in the number of pollen grains is a primary factor of the resistance to cool weather at the booting stage in the cultivars in the northern part of Japan. The results also suggested the existence of another genetic factor determining the resistance.

This report presents a brief description of SGW and TGW.SGW has many excellent characteristics of printability, light scattering, opacity, and high production yield, etc., compared to the chemical pulps. On the other hand, it has some unfavorable characteristics, such as low strength, poor weather resistance, and high power consumption, etc., However, it has been used effectively to make good opacity of paper in recent tendency toward light weight papers.TGW is made based on SGW to improve one of its defects, low strength. In the TGW process, similar to the PGW process, high temperature grinding, of which advantage is recognized in TMP, is applied to accelerate softening of lignin in a high temperature to give pulps higher strength. Besides the high temperature grinding, a feature of the TGW process is introduction of two process control methods, the chain feed control and the stability control for quality stabilization.

The twice electrodeposition (ED) coating is defined as that by which the primer was coated on the metallic material by ED, then the topcoat was coated on the wet, uncured primer by ED again. It can be observed by the distinction of deposition yield and the change of current density during each process. The main object of this method is to improve anticorrosion and weather resistance of coating film simultaneously. Comparing the physical and chemical properties, it was found that the film obtained by the twice ED coating has superior weather resistance to the one-coat electrodeposited film formed by a coemulsion. © 1997 John Wiley & Sons, Inc. J Appl Polm Sci 65:233–239, 1997

ポリエチレングリコール(PEG)およびジデシルジメチルアンモニウム塩(DDAC)系防腐剤により基材処理した木材(ペイマツ合板)について,透明系造膜塗料の耐候性の向上を検討した。2年間の屋外暴露試験において, 1%濃度のDDACのみによる基材処理では塗膜劣化が生じたが,PEG処理では10%において全ての暴露地で塗膜劣化をほぼ完全に抑制した。これは,PEGにより木材表面の耐光性が向上したためと考えられる。PEG濃度30%による処理では,旭川,富山,沖縄において塗膜剥離による塗装面劣化が生じたが,他の筑波,京都,鹿児島では10%濃度と同様に塗膜劣化は生じなかった。PEGは高い吸湿性を持っため,多雪地域や高温多湿地域ではPEGにより木材基材が吸湿し,塗膜剥離が生じやすくなると考えられる。このため, PEGによる基材処理では処理濃度および使用環境を考慮する必要がある。

Due to its higher photovoltaic efficiency, CPV has the advantage of needing a smaller panel footprint than fixed PV systems. This characteristic makes it ideal for use as an independent power supply in remote locations where transportation and site procurement present a challenge. The overall system needs to be compact and light without sacrificing weather resistance. Skilled personnel are scarce in remote areas, so easy setup and maintenance are also important. We have developed two techniques based on the notion of bio-mimicry. One is machine learning to counteract errors in installation position without the need for human intervention, and the other is a three-dimensional panel structure that cuts the wind load by up to 20%. We describe our experimental results gained in field tests.

This paper presents some results of a new porcelain insulator design applied to distribution networks in Brazil. The mechanical modeling allows the analysis of the flexural strength. In the electrical modeling an axi-symmetric electrostatic formulation is applied to study the porcelain insulator performances. This analysis allows to examine if the electric field values are above of the dielectric strength values of the material, which would result in the rupture of the dielectric. After this, the prototypes are manufactured based on the simulations and tested electrically according to Brazilian standard. The use of this new porcelain system in replacement of the current system presented the following characteristics: higher insulation weather resistance, higher safety, lower maintaining, the same installation cost, and the advantage of being more aesthetically pleasant.

The relationship between the amount of wind-driven rain or driving-rain and the driving-rain index (product of annual rainfall and mean wind speed) is studied. An analytical approach is proposed to obtain the relationship between these two quantities. It is observed that they are related by two factors, (a) the driving-rain coefficient and (b) the co-occurrence factor. The driving-rain coefficient is shown in the paper to be a function of drop size distribution which depends on the rainfall intensity and the type of rain. The co-occurrence factor describes the amount of correlation between wind and rain. The characteristics of wind and rain at four meteorological stations across Sydney, Australia are studied. The driving-rain characteristics for these sites are observed to be different. The amount of driving-rain for a given site is also found to be very different compass directions. They can differ by a factor of 10 and more. It is believed that for the purpose of weather resistance design of building facade, the directional driving-rain index should be used. Using the proposed method, the co-occurrence factor for the dominant driving-rain direction in Sydney is found to be 1.12 and the driving rain coefficient is calculated to be 0.204. With these two factors the amount of driving rain can be calculated from the driving-rain index.

Important material properties such as strength, elasticity, movement capability and weather resistance are developed as a sealant cures. Indeed, the magnitude of key material properties such as modulus is directly related to the level of cure. Hence it is important to appreciate the level of cure of a sealed joint when it is being tested. A review of the curing of sealants is given with some generalized cure mechanisms proposed for polysulfide, polyurethane and silicone sealants. There is generally very little published work on assessing the cure of sealants. The deficiencies in traditional methods for measuring the level of cure in polymer systems (for example, hardness and rheometry tests) when applied to sealants are outlined. Two alternative methods were used to determine the state of cure of six sealant materials: the measurement of modulus and glass transition temperature ( T g ) with cure time. The effect of different curing regimes on cure development was monitored for up to 16 weeks' cure time. The results show that both modulus and T g are useful parameters for assessing the cure level of sealants, with T g measurement being particularly elegant. Six weeks' curing appeared to be the minimum cure time necessary to provide a sufficiently high degree of cure for material testing to be performed, regardless of curing regime of sealant type used.