Incremental improvements

The first-stage catalysts for the oxidation to methacrolein are based on complex mixed metal oxides of molybdenum, bismuth, and iron, often with the addition of cobalt, nickel, antimony, tungsten, and an alkaU metal. Process optimization continues to be in the form of incremental improvements in catalyst yield and lifetime. Typically, a dilute stream, 5—10% of isobutylene tert-huty alcohol) in steam (10%) and air, is passed over the catalyst at 300—420°C. Conversion is often nearly quantitative, with selectivities to methacrolein ranging from 85% to better than 95% (114—118). Often there is accompanying selectivity to methacrylic acid of an additional 2—5%. A patent by Mitsui Toatsu Chemicals reports selectivity to methacrolein of better than 97% at conversions of 98.7% for a yield of methacrolein of nearly 96% (119). 

The ethylene-based, balanced vinyl chloride process, which accounts for nearly all capacity worldwide, has been practiced by a variety of vinyl chloride producers since the mid-1950s. The technology is mature, so that the probabiUty of significant changes is low. New developments in production technology will likely be based on incremental improvements in raw material and energy efficiency, environmental impact, safety, and process reUabiUty. 

A key advantage of the business process redesign approach is that while it draws on past experience (in the form of the team s collective expertise) it is not bound by it. This helps minimize the risk that inadequate practices may become institutionalized through habit or neglect, and forces the team to take a fresh look at the critical processes under review. At the same time, this approach requires more concentrated effort than either TQM or model programs and may not be necessary in cases where incremental improvement is all that s required to address PSM gaps. 

Quality Management approaches encourage a comprehensive review of a system. This comprehensive approach encourages the designers to question every aspect of a system. In this way, incremental improvements are quickly identified and by implementing new approaches dramatic improvement in performance can be achieved. 

Energy lost to mechanical friction has been decreased significantly through a large number of small, incremental improvements. In the typical modern engine, about half of the friction occurs between the cylinder wall and the piston/piston ring assembly. The sidew all contact surfaces of the piston... 

In ground transportation, the push for advanced-performance materials has been less dramatic because cost is the discriminator in the selection of components and systems. However, incremental improvement in automotive materials has been substantial in many areas, particularly in structural steels and plastics. 

A number of developments have increased the importance of capillary electrophoretic methods relative to pumped column methods in analysis. Interactions of analytes with the capillary wall are better understood, inspiring the development of means to minimize wall effects. Capillary electrophoresis (CE) has been standardized to the point of being useful as a routine technique. Incremental improvements in column coating techniques, buffer preparation, and injection techniques, combined with substantive advances in miniaturization and detection have potentiated rugged operation and high capacity massive parallelism in analysis. 

Some analytical methods are highly mature (NAA, XRD, XRF, XAS), the theory is well assessed, and just instrumental and incremental improvements (more intense sources, better detectors) may be expected. However, in many other areas the sharply increasing power of analytical instrumentation (with regard to both hardware and software) and its transformation into tools for in-process control (such as NIRS, LR-NMR, etc.) are most appropriately considered as breakthroughs. 

It must be emphasized that the formulation of three-center T-bonds provides a qualitative (not merely incremental) improvement in the accuracy of the natural Lewis-structure description of diborane. Because a three-center orbital is intrinsically more mathematically flexible than a two-center orbital, the description of any molecule is seemingly improved by employing three-center in place of two-center NBOs. However, for most non-boron molecules this improvement would be quite negligible (e.g., less than 0.1% for ethane, whose two-center Lewis-structure... 

The final consideration in operationalizing a taxon is the number of indicators. Generally, greater numbers are preferred. MAXCOV requires at least three indicators and simulations suggest that three may work reasonably well, but this number is far from ideal. In a large simulation study, Beauchaine and Beauchaine (2002) found that an increase in indicator numbers from three to four and from four to five produced considerable incremental improvement. However, six appeared to be a point of diminishing returns that is, five indicators performed almost as well as six. Moreover, MAXCOV outputs for six or more indicators are rather unwieldy. We believe it is better to have a few high quality indicators than to add low quality indicators to the set just to increase their number. 

A function of steady, incremental improvements in system and unit economics and operation... 

Boyes, Gai and coworkers at the University of Oxford (in association with JEOL Ltd) (33) and by Thomas and coworkers at the University of Cambridge (also in association with JEOL Ltd) (34,35). The key points of these developments were that the instrument had a resolution similar to that of the best home-built HRTEM instruments ( 2 A) at a small fraction of the cost, and it came in a user-friendly package, achieving the full theoretical performance routinely while fitting in a standard laboratory and requiring no special buildings. Incremental improvements in resolution (—1.3-1.6 A) were achieved later with the development of a 400-kV HRTEM (36). 

Since zeolite catalysts are successfully introduced in the refining and petrochemical industries, it is not surprising that most of the recent advances concern incremental improvements of existing processes with the development of new generations of catalysts (e.g., dewaxing, ethylbenzene and cumene synthesis). The number of newer applications is much more limited, for example, direct synthesis of phenol from benzene and aromatization of short-chain alkanes, etc. However, both the improvement and development of processes contribute significantly to environmental advances. 

As mentioned above, initial work in automating ECALE involved use of a thin-layer flow cell-deposition system. A thin layer cell was chosen because it allowed very small amounts of solution to be used in each step, minimizing the total volume of solution used to form a deposit. Development of an automated thin layer flow deposition system began early on and proceeded by a long sequence of incremental improvements (Fig. 19) [158]. 

Today s HPLC pumps have sophisticated designs honed by decades of incremental improvements. They are also more reliable and easier to maintain than their predecessors. Short seal life and check valve malfunctioning seen in the early models are no longer problems. In this section, the principle of pump operation is described with an emphasis on advances leading to higher reliability and performance. A discussion of system dwell volume is included. 

Rather, the success of fuel cell technology hinges on major breakthroughs, not incremental improvements, in design and implementation of advanced materials that are specifically optimized to meet targets in performance, operating conditions, lifetime, and cost. In particular, the required improvements would be impossible without advances in the... 

Consider the improvement of quality. Is it possible that small, incremental improvements might not individually show highly statistical significance, yet all of them taken as a whole might show a highly statistically significant effect ... 

IE provides a foundation for sustainable industrialization, not just incremental improvement in environmental management. The objectives of IE suggest a potential for reindustrialization in economies that have lost major components of their industrial base. Specifically, the objective of industrial ecology is not merely to reduce pollution and waste as traditionally conceived, it is to reduce throughput of all kinds of materials and fuels, whether they leave a site as products, emissions, or waste. 

Resistance to change is overcome and qnality management is achieved throngh the ongoing incremental improvement of the laboratory processes. 

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