Sodium molybdate—a possible alternate additive for sodium dichromate in the electrolytic production of sodium chlorate

Sodium dichromate is commonly used in sodium chlorate production to maintain high current efficiency; however, it is also a well documented carcinogen. To reduce the environmental impact, identification of a suitable alternative with similar buffering characteristics to dichromate and without adverse effect on the electrolytic performance of sodium chlorate production is important; sodium molybdate is a good candidate. Molybdate ion and its conjugated acid work as a buffer pair at pH 5–6, a lower and slightly narrower pH window than the typical buffer region of dichromate. Nonetheless, the molybdate buffer works effectively during the electrolytic process by maintaining pH at 5.9. Although the use of molybdate buffer will lower the overpotential of hydrogen evolution reaction (HER) by 100 mV, the average off-gas oxygen content is noticeably compromised at 3.6–4.6%, measured using a pilot cell operated at 3 kA m⁻²and 80 °C during a 3-day trial. The resulting current efficiency of 91 92% is significantly lower than when dichromate is employed as the process additive (> 96%). Mixtures of different dichromate and molybdate ratio were also investigated in terms of the resulting cathode surface potential.     

Bench-scale continuous hydrogenation of Australian coals — study of iron catalysts and recycle solvent composition

The inter-relations between iron catalysts, recycle solvent composition and product yield and composition have been investigated in bench-scale (1–2 kg h^?1) continuous hydrogenation of Australian coals at process severity of 21–22 MPa at 400–430°C. Products and recycle solvent are recovered in batch distillation (atmospheric and vacuum) and the distillate solvent is returned to slurry feed without further treatment. Successive samples of recycle solvent are analysed by g.c.-m.s., i.r. and titrimetry. The effect of adding iron catalysts in the form of red mud - sulphur mixtures or compounds after a short period of continuous operation without catalyst is demonstrated. Distillate yields from black coals increase from 24–34 wt% daf under non-catalytic conditions to 35–53 wt% daf by adding iron catalysts. The composition of the almost equilibrated recycle solvent also changes and a new equilibrium is approached after the iron catalyst is added. The effect of solvent composition on distillate yield can not be determined from these data. The ratio of hydroaromatic components to hydroaromatic plus aromatic components in the solvent increases from ≈0.2 at non-catalytic equilibrium to ≈0.5–0.6 at catalysed equilibrium after adding iron. Other compositional parameters in the recycle solvent do not show any clear responses to the addition of iron. Equilibrium solvent composition under constant operating conditions is attained at ≈10 passes at 1 kg ^h?1 throughput with total system holdup of ≈20 kg. Paraffins for the Queensland subbituminous coal equilibrated at 18–24% in the solvent, phenolics at 16–21%, basic nitrogen at ≈0.4% (as N), and the balance a mixture of aromatics and hydroaromatics. The total aromatics neglecting phenolics in the equilibrium recycle solvent consists of ≈40–50% each of two-and three-ring and 5–10% four-ring members.     

Designing a supply network artifact for data,process, and people integration

E-procurement and supplier-relationship management systems have helped to substantially advance process execution in supply management. However, current supply network systems still face challenges of high data integration efforts, as well as the decoupling of structured data and processes from the growing amount of digitalized unstructured interactions of supply management professionals. Inspired by the room for improvement posed by this challenges, our research proposes a design for a supply network artifact in supplier qualification that addresses these problems by enabling holistic integration of data, processes, and people. The artifact is developed following an action design research approach. Building on a set of meta-requirements derived from literature and practice explorations, we conceptualize two design principles and derive corresponding design decisions that have been implemented in an software artifact. Finally, we formulate testable hypotheses and evaluate the artifact and its design in the context of supplier qualification. Our results show that the proposed design reduces mental effort of supply management professionals and significantly increases efficiency when performing typical supply network tasks such as supplier qualification.     

Computing presentations for subgroups of polycyclic groups and of context-free groups

Algorithms for solving uniform decision problems for algebraic structures crucially depend on the chosen finite presentations for the structures under consideration. Rewriting techniques have been used very successfully to solve uniform decision problems, when the presentations considered involve finite, noetherian, and ()-confluent rewriting systems. Whenever the class of algebraic structures considered is closed under the operation of taking finitely generated substructures, then the algorithms for solving the uniform decision problems can be applied to the substructures as well. However, since these algorithms depend on the form of the presentations, this involves the task of constructing a presentation of a certain form for a substructure given a presentation of this form for the structure itself and a finite set of generating elements for the substructure.This problem, which has received a lot of attention in algebra, is here investigated from an algorithmic point of view. The structures considered are the following two classes of groups, which have been studied extensively before: the polycyclic groups and the context-free groups.Finitely generated context-free groups can be presented by finite, monadic, and -confluent string-rewriting systems. Due to their nice algorithmic properties these systems provide a way to effectively solve many decision problems for context-free groups. Since finitely generated subgroups of context-free groups are again contextfree, they can be presented in the same way. Here we describe a process that, from a finite, monadic, and -confluent string-rewriting system presenting a context-free groupG and a finite subsetU ofG, determines a presentation of this form for the subgroup U ofG that is generated byU. For finitely presented polycyclic groups we obtain an analogous result, when we use finite confluent PCP2-presentations to describe these groups.This work was performed while this author was visiting at the Fachbereich Informatik, Universität Kaiserslautern, during his sabbatical 1991/92     

Ultraviolet photodetectors and readout based on a-IGZO semiconductor technology

In this work, real-time ultraviolet photodetectors are realized through metal–semiconductor–metal (MSM) structures. Amorphous indium gallium zinc oxide (a-IGZO) is used as semiconductor material and gold as metal electrodes. The readout of an individual sensor is implemented by a transimpedance amplifier (TIA) consisting of an all-enhancement a-IGZO thin-film transistor (TFT) operational amplifier and a switched capacitor (SC) as feedback resistance. The photosensor and the transimpedance amplifier are both manufactured on glass substrates. The measured photosensor possesses a high responsivity R , a low response time t _{R E S} , and a good noise equivalent power value NEP .     

High-performance MEMS shutter display with metal-oxide thin-film transistors and optimized MEMS element

Active matrix prestressed microelectromechanical shutter displays enable outstanding optical properties as well as robust operating performance. The microelectromechanical systems (MEMS) shutter elements have been optimized for higher light outcoupling efficiency with lower operation voltage and higher pixel density. The MEMS elements have been co-fabricated with self-aligned metal-oxide thin-film transistors (TFTs). Several optimizations were required to integrate MEMS process without hampering the performance of both elements. The optimized display process requires only seven photolithographic masks with ensuring proper compatibility between MEMS shutter and metal-oxide TFT process.     

Second Sound Measurements Near the Tricritical Point in 3He-4He Mixtures

In this paper we discuss a pulsed second sound experiment, aimed at determining accurately the critical exponent , and the predicted logarithmic correction to scaling, for the superfluid density along a tricritical path in the ³ He- ⁴ He phase diagram. We present an accurate estimate for the limits for closest approach to the tricritical point, as set by gravitationally induced sample inhomogeneities and finite size effects, and discuss some of the complications associated with measurements close to the tricritical point.     

Insult, aggression, and the southern culture of honor: An "experimental ethnography."

Three experiments examined how norms characteristic of a "culture of honor" manifest themselves in the cognitions, emotions, behaviors, and physiological reactions of southern White males. Participants were University of Michigan students who grew up in the North or South. In 3 experiments, they were insulted by a confederate who bumped into the participant and called him an "asshole." Compared with northerners (who were relatively unaffected by the insult) southerners were more likely to think their masculine reputation was threatened, more upset (as shown by a rise in cortisol levels), more physiologically primed for aggression (as shown by a rise in testosterone levels), more cognitively primed for aggression, and more likely to engage in aggressive and dominant behavior. Findings highlight the insult–aggression cycle in cultures of honor, in which insults diminish a man's reputation and he tries to restore his status by aggressive or violent behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A fully integrated 1‐in. AMOLED display using current feedback based on a five‐mask LTPS CMOS process

Abstract— In the past, a five‐mask LTPS CMOS process requiring only one single ion‐doping step was used. Based on that process, all necessary components for the realization of a fully integrated AMOLED display using a 3T1C current‐feedback pixel circuit has recently been developed. The integrated data driver is based on a newly developed LTPS operational amplifier, which does not require any compensation for Vth or mobility variations. Only one operational amplifier per column is used to perform digital‐to‐analog conversion as well as current control. In order to achieve high‐precision analog behavior, the operational amplifier is embedded in a switched capacitor network. In addition to circuit verification by simulation and analytic analysis, a 1‐in. fully integrated AMOLED demonstrator was successfully built. To the best of the authors' knowledge, this is the first implementation of a fully integrated AMOLED display with current feedback.