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To study the changes occurring in lac‐polyvinyl butyral (PVB) resin blends at molecular levels on baking the blends at 200°C for different intervals of time. It was also to ascertain the changes in key physico‐chemical parameters of these blends, before and after applying thermal stress on these blends.

Films of lac‐PVB blends, applied on tin panels were baked at 200°C for different time intervals. The FTIR spectra of the blends were recorded using specular reflectance spectroscopic techniques. The results obtained were compared and reported. The blends were also tested for different physico‐chemical parameters such as scratch hardness, flexibility, adhesion, acid resistance, etc.

On baking the blends of lac‐PVB resin at 200°C for different time intervals; fragmentation reaction, that is breakdown of products into small molecules, takes place in lac‐PVB blends. Side products such as acetic acid emerge on baking the blends. Probably hydrolysis of oxirane ring also takes place leading to the release of free alcoholic groups. The lac‐PVB blends do not show any improvement in scratch hardness and are also not resistant to the action of acids. The blends made by lac‐PVB resin baked at 200°C do not seem to be compatible as no improvement in any of the physico‐chemical parameters was seen.

Mixtures of solvents were tried for dissolving the PVB resin. In most of the solvent mixtures, PVB resin forms big lumps and is not soluble so there is a need for universal solvent for dissolving the PVB resin. The spectral studies on lac‐PVB blends were conducted qualitatively, although desirable, quantitative studies could not be carried out, due to the inherent difficulties in handling the resins.

The parent resins in lac‐PVB blends (baked at 200°C) do not seem to be compatible with one another as there was no improvement in any of the physico‐chemical parameters of the lac‐PVB blends. For making lac‐PVB blends, low range of baking temperature may be tried.

In literature, there is not much evidence of making lac‐PVB blends. This paper is the first one in attempting to obtain and correlate FTIR spectra of the lac‐PVB blends with physico‐chemical changes of the blends. This paper also highlights the convenience of the method and the scope of sophisticated data analysis such as derivative spectrometry.

This experiment analyzes multi-offer versions of the signaling and screening litigation games, as well as a bilateral multi-offer litigation game. A plaintiff has either a low or a high claim on an uninformed defendant, and the two negotiate in an attempt to reach a pre-trial settlement. Trial is costly, and settlement generates surplus over which the two parties can bargain. In the signaling game, the defendant has the power to make the offer, while the plaintiff makes the offer in the screening game. Previous experiments on single-offer games find that disputes occur even when offers contain surplus not predicted under the theory, and fairness appears to be important in explaining deviations from theory. This research examines whether renegotiation in the form of successive sequential offers can yield efficiency gains via lower dispute rates. There are four main findings. One, under the one-sided multi-offer structure the excess dispute rate is 23 percentage-points lower in the screening game, and the high-offer dispute rate is 31 percentage-points lower in signaling game. The bilateral game yields an additional 15 percentage-point reduction in the high-offer dispute rate, but excess disputes persist. Two, in these games, proposers take advantage of the multi-offer opportunity and make around three to four offers per negotiation. Three, across games the surplus in a fair offer remains constant at about one-sixth of the surplus, but the empirical benchmark from which this is measured varies according to which player has the power to make the offer. In the one-sided games, the benchmark is the respective zero-surplus endpoint, but in the bilateral game the benchmark is the surplus midpoint. Fourth, dynamic behavior plays an important but complex role in observed outcomes. Multi-offer mechanisms may be alternatives to costly information transmission mechanisms like disclosure or discovery.

The purpose of this paper is to evaluate the effect of antioxidant 2,6-di-tert-butyl-p-methylphenol (BHT) on the thermal stability and fatigue resistance of spirooxazine and then study the properties of photochromic polyvinyl butyral resin (PVB) films.

BHT was introduced into the spirooxazine system by blending and covalent bonding. The properties of spirooxazine solutions and photochromic PVB films were studied.

The thermal stability and fatigue resistance of spirooxazine covalently linked (BHT-SO) or mixed (BHT/SO) with BHT were higher than the system without BHT, and BHT-SO was the better one. But acidic substance would greatly impair the fatigue resistance of spirooxazine. The optimum addition amount of BHT-SO2 to PVB was 2.5 per cent, and the minimum limit was 0.01 per cent. The fading kinetic and fatigue resistance of film were similar to the solution and better. Plasticizer could accelerate the fading rate and strengthen the mechanical properties of photochromic film but had no effect on the fatigue resistance.

Spirooxazine could be grafted onto the PVB chain to make the ring closure fading reaction slower.

In addition to the wide application prospects of photochromic materials in decoration, optical storage, etc., the photochromic PVB film in the car safety glass can absorb sunlight and turn blue, then fade to colorless when the sunlight disappears, making the interior environment more comfortable.

The introduction of BHT into the spirooxazine system not only exerts its ability to capture free radicals, but its bulky volume also increases the resistance of the ring closure, making the fading process slower.

The aim of this study is to extend the squeezing film problems between a long cylinder and an infinite plate, considering the piezo-viscous behavior (PVB) of the Barus experimental relationship.

By integrating the nonlinear Reynolds-type differential equation directly, an analytical film-pressure solution is obtained and applied to investigate the load-carrying capacity and the approaching time.

Compared with the case of constant-viscosity lubricants (CVLs), the effects of PVB are found to provide higher load-carrying capacities and longer approaching times for the squeezing films.

It is found that when the cylinder is squeezed to a dimensionless central film height of 0.3, the dimensionless approaching time required for the CVL case is 4.922. However, the effects of PVB (α 0.0001, 0.001, 0.005 and 0.01) provide longer approaching times with values of 8.324, 8.438, 9.028 and 10.079. The cylinder-plate squeeze film system considering the influences of PVB results in a longer operating life.

Just looking through a car's windshield does not give us much reason to wonder about how it is made. The idea that special manufacturing expertise might be required can hardly occur to anyone, but that is exactly what is needed to ensure crystal‐clear visibility, not to mention a perfect fit every time one is pressed into place on a car production line. Comprising two thin glass sheets joined by a vinyl interlayer, windshields are assembled – usually manually – to a very precise product and environmental specifications. To make sure this is done as perfectly as possible, the industry invests heavily in the equipment used for their fabrication. ABB has now developed a robot‐based Compact Assembling System for the automatic assembly of laminated windshields that speeds up production and increases cost efficiency.

The purpose of this paper is to examine the provision of audiovisual materials in UK public libraries and their economic value.

A questionnaire survey of all the public library authorities in the UK was used to investigate current provision of audiovisual material, expected future provision, and the amounts spent on and generated by audiovisual collections. Data collected, together with those available from other reputable sources, were then used to estimate the cost benefit or value of audiovisual provision.

The provision of audiovisual material in UK public libraries is widespread and varied. While audiovisual collections provide economic value and generate income from charging for loans, there are significant costs inherent in providing such services. Concerns are raised about the constant developments in media formats and the ability to make adequate provision. A cost benefit of 1:1.34 using the PVB (present value benefits) based on maximum loan charges was found, meaning that the UK gets £1.34 direct benefit from every £1.00 spent on the audiovisual service.

There are different methods used by economists to estimate value of public services, all having limitations. The method used in this research is no exception. The cost‐benefit ratio found is based on maximum loan charges. However, this figure would be higher if the PVB had been based on purchase costs or lower if the PVB had been based on mean loan charges. Further, the figures do not include indirect benefits or option benefits, so are likely to be underestimates of the true cost benefit of the audiovisual service.

This research is likely to be of interest to public library managers and funding bodies needing evidence for the value of audiovisual provision.

This is the first attempt to put a monetary value on audiovisual provision in the UK. It also provides insights into current and future audiovisual provision.

A sol-gel process has been successfully utilized to form hybrid materials of poly(vinyl butyral) (PVB) and zirconium dioxide (zirconia). The gelation occurred due to the interaction between remaining hydroxyl group of PVB and zirconia. The hybrids showed good optical transparency and significant improvement in Young's modulus, dynamic mechanical property, abrasion resistance and impact resistance. The glass transition temperature of PVB shifted to higher temperatures by hybridization of PVB and zirconia.

Cost-benefit (C/B) analysis helps to determine the economic feasibility of business software investments. Research literature and published practices do not recognize substantial software maintenance costs in C/B analysis. Current analyses emphasize the benefits of an initial investment but do not consider the recurring benefits of each enhancement during the software lifecycle. Such analyses could lead to incorrect investment decisions and lost business opportunities. This article aims to review current research on software lifecycle costs and develop a theoretically sound C/B analysis.

This article reviews current C/B analyses and discusses their shortcomings in treating the significant recurring maintenance costs. It analyzes the findings of various studies on software maintenance and synthesizes these findings to identify the nature of various maintenance costs and their benefits. Based on the synthesis, it theorizes various cost and benefit elements for inclusion in a revised C/B analysis.

This article identifies each recurring maintenance cost relevant to C/B analysis. It also identifies recurring benefits from each enhancement that hitherto have been omitted. Finally, this article discusses how these costs and benefits should be treated in the revised C/Bs analysis.

This is a conceptual paper proposing a new C/B analysis and requires an empirical validation.

This article provides a revision of the C/B analysis that is long overdue. It will help to justify a software investment correctly, rank software projects that compete for limited funds and help create a sound software project portfolio. Since 20% of software products may incur 80% of software investment, this analysis will help to make correct software investments and avoid lost business opportunities. This article also describes a practical method to use the revised C/B analysis.

This article provides a revision of the C/B analysis that is long overdue. It will help to justify a software investment correctly, rank software projects that compete for limited funds and help create a sound software project portfolio. Since 20% of software products may incur 80% of software investment, this analysis will help to make correct software investments and avoid lost business opportunities. This article also describes a practical method to use the revised C/B analysis.

This paper aims to analyze the bearing characteristics of the high speed train window glass under aerodynamic load effects.

In order to obtain the dynamic strain response of passenger compartment window glass during high-speed train crossing the tunnel, taking the passenger compartment window glass of the CRH3 high speed train on Wuhan–Guangzhou High Speed Railway as the research object, this study tests the strain dynamic response and maximum principal stress of the high speed train passing through the tunnel entrance and exit, the tunnel and tunnel groups as well as trains meeting in the tunnel at an average speed of 300 km·h-1.

The results show that while crossing the tunnel, the passenger compartment window glass of high speed train is subjected to the alternating action of positive and negative air pressures, which shows the typical mechanic characteristics of the alternating fatigue stress of positive-negative transient strain. The maximum principal stress of passenger compartment window glass for high speed train caused by tunnel aerodynamic effects does not exceed 5 MPa, and the maximum value occurs at the corresponding time of crossing the tunnel groups. The high speed train window glass bears medium and low strain rates under the action of tunnel aerodynamic effects, while the maximum strain rate occurs at the meeting moment when the window glass meets the train head approaching from the opposite side in the tunnel. The shear modulus of laminated glass PVB film that makes up high speed train window glass is sensitive to the temperature and action time. The dynamically equivalent thickness and stiffness of the laminated glass and the dynamic bearing capacity of the window glass decrease with the increase of the action time under tunnel aerodynamic pressure. Thus, the influence of the loading action time and fatigue under tunnel aerodynamic effects on the glass strength should be considered in the design for the bearing performance of high speed train window glass.

The research results provide data support for the analysis of mechanical characteristics, damage mechanism, strength design and structural optimization of high speed train glass.