Conventional Handling Research Articles

MTBE and Other Oxygenates: Environmental Sources, Analysis, Occurrence, and Treatment

The production and use of fuel oxygenates has increased dramatically since the early 1990s due to federal and state regulations aimed to improve air quality. Currently, methyl tert-butyl ether (MTBE) is the most widely used oxygenate in gasoline, followed by ethanol. Widespread use of oxygenates in gasoline has been accompanied by widespread release of these materials into the environment. This manuscript provides a review of environmental sources of MTBE and alternative oxygenates, analytical methods available for their detection in environmental samples, their occurrence in the environment with a focus on groundwater, and treatment methods for their removal from gasoline-contaminated water. Accidental gasoline releases from underground storage tanks and pipelines are the most significant point sources of oxygenates in groundwater. Because of their polar characteristics, oxygenates migrate through aquifers with minimal retardation, raising great concerns nationwide of their potential for reaching drinking water sources. As a group, fuel oxygenates present distinct analytical and sample preparation issues. Conventional procedures for the analysis of gasoline constituents have been shown to be insensitive for fuel oxygenates, and ether hydrolysis to alcohol under acidic conditions has led to a reassessment of conventional handling techniques for groundwater samples. An evaluation of MTBE's occurrence in drinking water sources over time in three states showed that the frequency of MTBE detection since 1999 appears to be stabilizing in groundwater and slightly decreasing over time in surface water. Recent studies have demonstrated the effectiveness of conventional treatment technologies and the promise of emerging technologies for MTBE removal from contaminated media. However, the removal from water of tert-butyl alcohol (TBA), an impurity in MTBE-blended fuels and an MTBE breakdown product, can be problematic using some conventional technologies such as air stripping and granular activated carbon. These limitations may generate additional problems for water purveyors, regulators, and site managers.

Ergonomic handle for an arthroscopic cutter

From an analysis of the routinely performed meniscectomy procedures, it was concluded that a punch with a side-ways steerable tip would improve the reachability of meniscal tissue. This potentially leads to a safer and more efficient meniscectomy. Furthermore, the current scissors handles of arthroscopic punches are ergonomically not sufficient. An ergonomic handle is designed with one lever that enables opening and closing of the instrument tip, and side-ways steering of the instrument tip. The design of the handle complies with ergonomic guidelines that were found in the literature. A model of the instrument tip was added to the new handle for comparison with conventional handles. Experiments were performed with a knee joint model, using objective and subjective criteria. The results show that the concept of a side-ways steerable punch is promising, since faster task times are achieved without increasing the risk of damaging healthy tissue. The current design of the ergonomic handle incorporates two degrees of freedom in an intuitive way, the handle is more comfortable to hold, and easy to control. The external memory capabilities of the new handle could be improved. Further development of this handle and the addition of a sufficient instrument tip and force transmission are recommended.

Ergonomic handle for an arthroscopic cutter

From an analysis of the routinely performed meniscectomy procedures, it was concluded that a punch with a side-ways steerable tip would improve the reachability of meniscal tissue. This potentially leads to a safer and more efficient meniscectomy. Furthermore, the current scissors handles of arthroscopic punches are ergonomically not sufficient. An ergonomic handle is designed with one lever that enables opening and closing of the instrument tip, and side-ways steering of the instrument tip. The design of the handle complies with ergonomic guidelines that were found in the literature. A model of the instrument tip was added to the new handle for comparison with conventional handles. Experiments were performed with a knee joint model, using objective and subjective criteria. The results show that the concept of a side-ways steerable punch is promising, since faster task times are achieved without increasing the risk of damaging healthy tissue. The current design of the ergonomic handle incorporates two degrees of freedom in an intuitive way, the handle is more comfortable to hold, and easy to control. The external memory capabilities of the new handle could be improved. Further development of this handle and the addition of a sufficient instrument tip and force transmission are recommended.

Multi-task flow system for potentiometric analysis: its application to the determination of vitamin B6 in pharmaceuticals.

A flow set-up based on the sequential injection analysis concept was designed, aiming at increased automation and robustness of procedures related with potentiometric detection in pharmaceutical control. In this sense, programmable set-up calibration, ion-selective electrode characterization, standard addition techniques and titration procedures could be carried out without any stock solutions conventional handling or modification on the physical structure of the flow system. Evaluation of a flow-through vitamin B6 selective electrode and its application to routine analysis of pharmaceuticals were selected as models to demonstrate the system potentialities. The system ability to generate in-line calibrating solutions was verified by comparing the results with those obtained with solutions prepared by the manual procedure. The vitamin B6 determination in pharmaceutical products was carried out and in-line performed recoveries gave values within 97.4-103.5%. The system ability to perform titrations was ascertained using the precipitation reaction of vitamin B6 with tetraphenylborate. Other profitable features such as lower reagent consumption with a low effluent generation volume were also achieved.

R.H. divertor maintenance – the divertor refurbishment platform

The ITER divertor assembly consists in 60 cassettes located in the bottom region of the vacuum vessel. Because of erosion and damage during, reactor operations, their replacement is expected to be required eight times during the machine lifetime. The cassettes will be withdrawn from the vessel through dedicated ducts and they will be transported to a hot cell for refurbishment. The divertor refurbishment platform (DRP) simulates the arrangement in the divertor hot cell for cassette inspection, component replacement and repair, measuring, and testing. The DRP had to demonstrate the feasibility of divertor cassette refurbishment, procedures, and the use of conventional remote handling equipment in a hot cell, for the refurbishment of high heat flux components (also called plasma facing components PFC), cassette locking systems, water feeds and post-repair, integrity testing. The true environmental conditions (temperature, atmosphere, radiation, contamination) have not been replicated in the DRP, but they were taken into account in the development of the mock ups, the remote handling equipment, and the operating procedures. The results permit to validate the hot cell operations for the cassette refurbishment and to specify the hot cell requirements. This paper describes the objectives, lay-out, test programme, test results, and future activities of the divertor refurbishment platform.

A constitutive model for the non-shock ignition and mechanical response of high explosives

An understanding of the non-shock ignition properties of energetic particulate composite materials, high explosives such as PBX-9501 is an important part of the safety assessments for conventional handling (transportation, storage, etc.) of weapons systems including assembly operations. This paper develops and demonstrates the use of a numerical constitutive model for PBX-9501 that includes viscoelastic response, statistical fracture mechanics, and an ignition hot-spot mechanism. The intent is that this model can be used in safety analyses involving accidents to prevent undesirable dispersion of Pu. The parameters have been determined that will predict the mechanical response and ignition:non-ignition of a set of experiments that have explored the non-shock properties of this material.

Knowledge management: a dilemma

Many activities are loosely called knowledge management, some of which are truly new ways of regarding information and knowledge while others are merely name changes or attempts to enhance the value and status of existing activities. Considers ways in which companies have introduced knowledge management: the management levels in which it resides; and its relationship with information technology and conventional data handling. Knowledge managers must ready themselves for dramatic changes and position all their services and activities carefully if they are to gain the full advantages of the technique.

A comparison between conventional and advanced handling systems for low volume container maritime terminals

In this paper a conventional low volume maritime terminal equipped with straddle carriers is compared against an advanced automatic stacking crane/automatic guided vehicle alternative. For both configurations a convenient layout was designed, a reasonable level of service (common for both terminals) was adopted, and the required amount of equipment was determined using computer simulation. The results indicate that the total cost per container and the area requirements do not differ considerably between the two configurations although there exist differences in the investment capital and the personnel required.

Growth into Miniaturization — Flexible Microassembly Automation

The particular problems which occur during the assembly of miniaturized components result from their small dimensions, their high sensitivity to damage and the micron-range precision required in the assembly process. Examples are provided to illustrate strategies for flexible micro-assembly automation: the implementation of new, problem-oriented assembly techniques and components and the optimization of conventional handling systems. The accuracy attainable by an automated micro-assembly system depends decisively on the ability to compensate for inevitable handling tolerances. Active as well as passive techniques for compensating tolerances during micro-assembly have been examined and their operating limits will be described. The precision assembly of a modern radio-controlled wrist watch will serve as an example of developments in assembly modules.

The Effect of Egg Limitation on Stability in Insect Host-Parasitoid Population Models

1. We investigate the potential effects of parasitoid egg limitation on host-parasitoid population dynamics. We define a parasitoid as egg-limited if a shortage of eggs means that at some time she cannot utilize an opportunity to oviposit. 2. We develop models which consider the differing physiologies of pro-ovigenic and synovigenic parasitoids to investigate the potential consequences of egg limitation. Pro-ovigenic parasitoids emerge with their full complement of mature eggs. Synovigenic parasitoids also emerge with some eggs, but can mature more later in life. 3. The models indicate that egg limitation in pro-ovigenic parasitoids has no effect on stability. This result is independent of the egg load distribution in newly emerged parasitoids, and of the maximum number of eggs with which a female emerges. In synovigenic models, however, egg limitation is found to be destabilizing, though the reduction in stability is decreased by (i) an increase in egg load at emergence, and (ii) a decrease in the 'latent' time required for egg maturation and gut emptying following a host meal. The latent period, during which time the full gut precludes feeding on hosts, differs from a conventional handling time in that host attacks (via oviposition) are still possible if the female has mature eggs. The maximum ovary storage capacity of females in a synovigenic parasitoid population has no effect on stability.

Handling Farmer Stock Peanuts at Warehouses with Potato Equipment1

Abstract An alternative system for handling farmer stock peanuts in and out of warehouse storage was evaluated and compared to conventional handling systems. The potato handling system provided significantly less mechanical damage and improved peanut value than conventional handling methods. Loose shelled kernels and sound splits were decreased by 1.83 and 4.00%. respectively, by more gentle handling of the peanuts (P≤0.05). Thus, the potential for aflatoxin contamination during storage was reduced. Economic analysis revealed that investment costs of the potato and conventional handling systems were similar. The analysis revealed that the net value of peanuts from a 3629-t capacity warehouse could be increased by $23,758/yr by investing in potato handling equipment instead of conventional handling equipment when constructing a new warehouse. However, it is probably not economically feasible to convert the handling equipment of an existing conventional warehouse to the potato handling system.

Performance-based exposure control limits for pharmaceutical active ingredients.

For many years pharmaceutical companies have established employee exposure limits for the active ingredients used in their products. Historically these limits were derived using traditional risk assessment methods. Because the trend in the pharmaceutical industry is to identify and develop more selective drugs of increasing potency, and because of the difficulty in identifying no-effect levels for certain drugs, a new performance-based approach for setting limits was developed. This method involves assigning materials into one of five hazard categories according to their inherent toxicological and pharmacological properties. The criteria used to assign compounds into performance-based exposure control limit (PB-ECL) categories focus on the degree to which exposure impacts human health. These assignments dictate the level of containment required to assure employee safety that is achieved through the use of engineering controls and safe handling practices. Several matrices were developed to specify general design concepts and controls for unit operations in laboratory and manufacturing operations. Containment options range from conventional handling practices for low potency (PB-ECL Category 1) materials, to technologically advanced systems that result in essentially no open handling for potent or toxic (PB-ECL Category 3) materials, to state-of-the-art facilities employing closed processes and use of robotics for extremely potent (PB-ECL Category 5) materials.

Performance-Based Exposure Control Limits for Pharmaceutical Active Ingredients

For many years pharmaceutical companies have established employee exposure limits for the active ingredients used in their products. Historically these limits were derived using traditional risk assessment methods. Because the trend in the pharmaceutical industry is to identify and develop more selective drugs of increasing potency, and because of the difficulty in identifying no-effect levels for certain drugs, a new performance-based approach for setting limits was developed. This method involves assigning materials into one of five hazard categories according to their inherent toxicological and pharmacological properties. The criteria used to assign compounds into performance-based exposure control limit (PB-ECL) categories focus on the degree to which exposure impacts human health. These assignments dictate the level of containment required to assure employee safety that is achieved through the use of engineering controls and safe handling practices. Several matrices were developed to specify general design concepts and controls for unit operations in laboratory and manufacturing operations. Containment options range from conventional handling practices for low potency (PB-ECL Category 1) materials, to technologically advanced systems that result in essentially no open handling for potent or toxic (PB-ECL Category 3) materials, to state-of-the-art facilities employing closed processes and use of robotics for extremely potent (PB-ECL Category 5) materials.

Performance analysis of a LIM-based high-speed tool delivery system for machining

Material handling provides a major opportunity for productivity improvement in manufacturing systems. The poor performance of the conventional material handling systems, such as conveyors or automated guided vehicles, has led most researchers to focus on opitmal utilization of the material handling system through the design of new scheduling algorithms or control strategies. The low speed of currently available material handling systems is one of the major factors that lead to long process delays and correspondingly large work-in-process inventories common in many manufacturing systems. In this paper, we suggest a new design of material handling systems, driven by a high performance linear induction motor (LIM). The high speed of this LIM-based material handling system distinguishes it from the conventional material handling systems. To evaluate its performance, we have constructed a simulation model where the LIM-based vehicles serve as a tool delivery system in a flexible manufacturing system (FMS). We ...

Design and sizing of ergonomic handles for hand tools

In this paper, handles for two commonly used hand tools, the chisel and the off-set pliers, are designed using ergonomic principles. These were sized for both males and females falling in the 5th percentile, 50th percentile and 95th percentile groupings. The stresses developed in the ergonomically designed chisel handle while in use were analysed to verify the validity of the design. This chisel handle was then manufactured, and preliminary evaluation using electromyography was conducted. In these tests, the stresses exerted on the flexor and extensor muscles of the arm were measured and compared with those obtained during the use of a conventional handle. Under similar working conditions, results clearly showed that the ergonomically designed handle allows higher working efficiency than existing handles.

The versatile wax rim handle: impression making, tooth selection, and setup.

T he use of wax rims instead of conventional handles on custom impression trays has been advocated as an aid in the making of final impressions for complete dentures.‘*2 This article describes the expanded use of wax rim handles to include the accurate selection of denture teeth, the mounting of the maxillary cast using a face-bow transfer index, and ultimately as a guide for the setup of the maxillary anterior teeth.

Evaluation of Bent Hammer Handles

John Bennett has developed a family of handles with a 19 degree bend. This study evaluated acceptance of the 19 degree bend in two hammers (one normal length and one short) vs a conventional handle. After hammering nails with all three hammers, 104 subjects completed a 10 item semantic-differential questionnaire. Defining the vote for the conventional hammer as 100%, the vote for the short Bennett hammer was 110% and the normal length Bennett hammer was 113%. Personal characteristics were related to preference. People like the Bennett handles if they were younger and female. The short handle also was more preferred by heavier weight people and people with less hammering experience.

YIELD AND PALATABILITY OF HOT‐PROCESSED, PHOSPHATE‐INJECTED PORK

ABSTRACTHot‐processed pork carcass sides yielded 1.6% more retail cuts, had 1.8% less cutting and chilling loss and required 42.7% less heat energy and 39.5% less refrigeration energy than sides chilled to 4°C before being processed. Hot processing did not affect any cooking or palatability trait studied. Injection of loins to 110% of their weight with a 5% solution of sodium hexametaphosphate and sodium pyrophosphate produced juicier, more tender, heavier chops with more thaw loss, less browning during cooking, less desirable flavor, and higher microbial numbers than conventional handling of loins (P < 0.05). Phosphate injection did not affect (P < 0.05) overall acceptability or cooking losses of the loin chops but flavor desirability declined with storage time.

A STUDY ON “COLD FEEL” OF FABRICS

An apparatus for cold feel test of fabrics was designed in our laboratory. Seventeen chromel-alumel thermocouples connected in series were sandwiched between acrylic resin films, and bonded on a copper plate. The surface temperature of this copper plate was used as the hot plate in the apparatus and was controlled at 35°C with a heat source placed under it. Cooling curves showing the temperature change of the thermocouples just after putting a fabric on the hot plate were recorded under various conditions for different types of fabric.The results obtained are summarized as follows.1. Abrupt temperature change at initial few seconds can be measured exactly with this apparatus.2. The cooling curves recorded with this apparatus show a little increase of the surface temperature in a few seconds and seem to represent the real cold feel of a fabric at handling. Cold feel of a fabric may be estimated from the maximum cooling rate and maximum temperature drop obtained from this cooling curve.3. Cooling curves are affected by the material of the plate placed at the back of the fabric, the contact pressure between the hot plate and the fabric, and ambient relative humidity.The true contact area between the hot plate and a fabric is very small (0.005% of the apparent contact area). Therefore, the increase of the cooling rate by increasing the contact pressure may be caused mainly by the decrease of air gap between the hot plate and the fabric.4. To clarify the relation between this testing method and conventional handling test, more experiment and further theoretical consideration of this mechanism are required.

The Performance of Steelworks Equipment in Service

The processes of an integrated steelworks are coking, sintering, smelting, refining and re-heating for rolling. Most of the machinery is conventional or specialized mechanical handling equipment and rolling is a special form of such mechanical handling. Such equipment is an assembly of basic mechanisms such as shafts, bearings, couplings, gears, brakes and hydraulic actuators. The paper gives experiences in service of these mechanisms and deals more generally with the E.O.T. cranes which play a large part in the handling of steel from one process to the next. These experiences are drawn from the Spencer Steelworks which went into production in 1962.