Stickiness – A Comparison of Test Methods and Characterisation Parameters

ABSTRACT

The stickiness of adipic acid and alumina was tested in equipment for powder characterisation. Experiments covered various moisture contents at ambient temperature. Both wall adhesion and internal cohesion tests were carried out. The testers evaluated were the Jenike and Peschl shear cells, the Warren Spring Laboratory Cohesion tester, the unconfined yield strength tester, and the Teesside Laminated shear cell. In addition, the empirical tests put forward by Can (1) were carried out. The sticky-point temperatures of various amorphous materials were also tested.

The Jenike shear cell and the Warren Spring Cohesion tesm gave the most consistent and repeatable results for cohesion. None of the equipment tested gave a simple and repeatable measure of adhesion. The tester developed by Howe et al (2) determined the sticky-point quickly and repeatably.

Fluidisation tests were carried out in a small scale visualisation module. The results correlated well with the measured cohesion parameters.     

Applications of the Biosorption Process for Nickel Removal from Aqueous Solutions – A Review

Wastewaters and contaminants released to the aqueous environment increase due to developing industrialization and technology. These wastewaters should be treated before being discharged to water bodies. Also, reusable materials in wastewaters must be recovered by appropriate techniques. Discharge limits required by the authorities become more stringent with updated legislations. Nickel ions can be reusable by recovering it after the biosorption process. So, this will prevent the loss of raw materials in industries and it also affects the economy in a positive way. Conventional heavy metal removal processes may be costly and inadequate to meet the desired discharge limits and they exhibit low efficiencies. Eco-friendly and economical treatment technologies gain great importance in the removal and recovery of nickel from wastewaters. In this study, biosorption which is the subject of numerous studies and one of the heavy metal removal methods will be investigated, and nickel removal by this technique and the biosorption mechanism will also be elaborated with data from literature studies.     

Steady‐State and Dynamic Reactor Models for Hydrotreatment of Oil Fractions: A Review

The modeling of catalytic hydrotreatment reactors for petroleum fractions have been classified in several ways, for example steady‐state and dynamic, pseudohomogeneous, and heterogeneous, and so on. Depending on the system to be modeled, operating conditions and type of feedstock, these approaches could exhibit some advantages and disadvantages, wide scopes and limitations. In this review, the discussion about those modeling aspects, already published, is used to develop a generalized reactor model, which can be simplified in order to derive each single model previously reported. Some guides to estimate model parameters are also given.     

Can the Synchrony of Nitrogen Supply and Crop Demand be Improved in Legume and Fertilizer-based Agroecosystems? A Review

Asynchrony between nitrogen (N) supply and crop demand is the source of many environmental hazards associated with excess N in the biosphere. In this review, we explore some of the complexity of the synchrony issue in agroecosystems that obtain N via legume rotations or synthetic fertilizers. Studies that have simultaneously compared the fate of both sources of N suggest that in rainfed agricultures, crops recover more N from fertilizer, but a higher proportion of the legume N is retained in the soil and N losses tend not to differ greatly from either source. However, investigations from irrigated cropping systems indicate that legume N is generally less susceptible to loss processes than fertilizers. Such general conclusions need to be qualified by acknowledging that not all comparative studies have used ȁ8best management practices’ when applying the fertilizer or legume residues. When information-intensive management approaches are used, fertilizer-based systems can potentially out-perform the synchrony achieved by legume-based rotations. We suggest that the inclusion of perennials in cropping systems may hold the greatest promise for decreasing the risk of N losses in future farming systems.     

A Multi-layer Information Integration Platform for Chemical Process Operation Systems

In the process industry, automation and process control systems are widely implemented, information integration is however far away from satisfactory. It remains a hard job for senior managers to make decisions based on the plant-wide real-time integrated information. This paper proposes a multi-layer information integration platform. In the data integration level, the standard for the exchange of product (STEP) and the extensible markup language (XML) are used to unify these data of the chemical process. In the model integration level, the models are integrated by using the neutral model repository and CAPE-OPEN. In the integration of process task, the common object request broker architecture (CORBA) is used as the communication mediator. The XML is taken as the data standard. A uniform information platform is thus constructed and realized. The proposed information integration platform is satisfactorily implemented to solve the Tennessee Eastman (TE) problem.     

Electroless Nickel Plating – A Review

The operating process, versatility and the increasing research interest in optimising the process and products technology in the electroless plating method of metal coating, particularly, the electroless nickel plating of metallic substrates such as mild steel, necessitates the writing of this review. It is also aimed at providing more literature information, both of the past and the present published research in this field. In this paper, electroless nickel plating is introduced. The various nickel plating solutions and baths’ operating parameters; main types of electroless nickel plating; the mechanism involved in the plating process; application of the nickel plating process to iron powders; advantages and disadvantages and the process’s other applications are reviewed. Electroless nickel plating produces an amorphous deposit in the as-plated condition. The deposit is not dependent on current distribution and hence it is almost uniform in thickness. Electroless nickel plating is far more difficult to remove chemically than conventional nickel deposits due to its superior corrosion resistance. The deposit has a good wettability and is generally hard. However, its bath control is more complex than with electroplating. The bath also has lower efficiency and higher operating costs, even without the use of electricity.     

Comminution of Wood – Influence of Process Parameters

An essential element for sustainable use of renewable resources is an efficient comminution process for which the relation between energy input and size reduction is of great importance. Fine comminution of beech, oak, and spruce wood chips in cutting and hammer mills at different moisture content levels is investigated. The influence of the different process parameters as well as the size reduction performed by the hammer and cutting mill on the specific comminution energy is reported and the particulate properties of the comminution products are reported. Considering the energy requirements, functional relations were derived from the experimental results, which describe the relation between comminution energy and size reduction.     

Influence of Industrial and Agricultural by-Products as Cementitious Blends in Self-Compacting Concrete – A Review

Silicon - Globally, the annual generation of industrial and agricultural by-products is exceeding a thousand million tons and forecasted to tremendously inflate in the future. The by-products are...     

The Occurrence of 16 EPA PAHs in Food – A Review

Occurrence and toxicity of polycyclic aromatic hydrocarbons (PAHs) have been extensively studied in countries all over the world. PAHs generally occur in complex mixtures which may consist of hundreds of compounds. The U.S. Environmental Protection Agency (EPA) proposed in the 1970 to monitor a set of 16 PAHs which are frequently found in environmental samples. This article reviews the suitability of the 16 EPA PAHs for the assessment of potential health threats to humans stemming from the exposure to PAHs by food ingestion. It presents details on analysis methods, the occurrence of PAHs in food, regulatory aspects, and related risk management approaches. In addition, consideration is given to newer evaluations of the toxicity of PAHs and the requirements for risk assessment and management stemming from them.     

Solvent-impregnated resins (SIRs) – Methods of preparation and their applications

Interest in the development of solvent-impregnated resins (SIRs) and their applications for the separation of metal ions and organic compounds from water in the form of a hybrid polymeric adsorbent material has intensified over the past thirty years. SIRs are particulate adsorbers that possess a combination of the advantageous features of both liquid–liquid extraction and ion exchange and this renders them applicable to a wide range of potential liquid–solid separation and recovery processes. This paper reviews the extensive published literature on methods of synthesis of SIRs, attempts to stabilize hybrid solvent-impregnated resins and various applications of SIRs.     

Function-integrative Lightweight Engineering – Design Methods and Applications

Function-integrative lightweight engineering represents an essential element in modern design methods. Currently, there is a great need for the incorporation of sensors, actuators and electronics in novel, demand-oriented components. In contrast to a subsequent, mostly adhesive bonding, structural integration offers numerous advantages, for example in terms of space requirements and robustness. This paper demonstrates the potential of integrated sensors for various industrial sectors based on selected examples from mechanical engineering, aviation, mobility, sports, and medical technology.     

How to Investigate the Setting Kinetics of Refractory Castables——A Review of Methods and Their Relevancy for Technical Use

This article contributes to a meaningful interpretation of results gathered by in-situ measurements of sonic velocity,electrical conductivity and the change of temperature during setting and curing of LC refractory castables. All said monitoring techniques are well known in the refractory community and are well documented in the literature. However,the time dependent changes of the said properties are not well correlated to mineralogical and in consequence technological changes of the material during setting and curing. The basic interest of refractory users of course is to define the time at which the installation or the pre-shape construction element can be demoulded. This is in principle possible with the methods listed above. However,after water addition the time dependent changes of sonic velocity,electrical conductivity and temperature are diverse as there are possible combinations of cements,microfines and surface-active additives. In further the ambient conditions,temperature and relative humidity have a strong influence on these properties and this does not only mean a simple time-shift. Up to now the results are more confusing than helpful to determine the best time for demoulding pre-shapes and refractory linings. Recent research at Koblenz University of Applied Science contributes to a deeper understanding of the setting behaviour,because besides the physical evolution of the said parameters the time dependent formation of hydrate phases is also investigated by means of gravi-metric method. The proposed presentation will show detailed insights in the evolution of refractory castables during setting and curing.Key words: refractory; setting kinetics; hydrate bond water     

Adhesively bonded connections in the context of timber engineering – A Review

If there is one domain of civil engineering in which adhesives are currently booming, then it is timber engineering. Natural adhesives have been used for centuries to structurally connect timber elements, a trend that culminated in the beginning of the 20th century with the introduction of glue-laminated beams. With the introduction of synthetic adhesives, and their increasing economic success after World War II, a wide range of products is now available that have the potential to free timber engineering from most of its structural and size limitations. This review article is intended to shed some light on the current state-of-the-art regarding adhesively bonded connections in the context of timber engineering. First, the relevant properties of timber as an adherend are discussed, then different – including several hybrid – approaches for structurally jointing timber are illustrated and finally, different design approaches are presented.     

Biohydrogen Production from Organic Waste – A Review

Hydrogen fuel is a promising alternative to fossil fuels because of its energy content, clean nature, and fuel efficiency. However, it is not readily available. Most current producion processes are very energy intensive and emit carbon dioxide. Therefore, this article reviews technological options for hydrogen production that are eco-friendly and generate clean hydrogen fuel. Biological methods, such different fermentation processes and photolysis are discussed together with the required substrates and the process efficiency.     

Distinct Dynamic and Conformational Features of Human STING in Response to 2′3′-cGAMP and c-di-GMP

The human stimulator of interferon genes protein (hSTING) can bind cyclic dinucleotides (CDNs) to activate the production of type I interferons and inflammatory cytokines. These CDNs can be either bacterial secondary messengers, 3′3′-CDNs, or endogenous 2′3′-cGAMP. cGAMP, with a unique 2′–5′ bond, is the most potent activator of hSTING among all CDNs. However, current understanding of the molecular principles underlying the unique ability of 2′3′-cGAMP to potently activate hSTINGs other than 3′3′-CDNs remains incomplete. In this work, molecular dynamics simulations were used to provide an atomistic picture of the binding of 2′3′-cGAMP and one 3′3′-CDN (c-di-GMP) to hSTING. The results suggest that hSTING binds more strongly to 2′3′-cGAMP than to c-di-GMP, which prefers to bind with a more open and flexible state of hSTING. Finally, a potential “dock–lock–anchor” mechanism is proposed for the activation of hSTING upon the binding of a potent ligand. It is believed that deep insights into understanding the binding of hSTING with 3′3′-CDNs and the endogenous 2′3′-cGAMP would help to establish the principles underlying powerful 2′3′-cGAMP signaling and the nature of hSTING activation, as well as related drug design.     

Armor Options: A Comparison of the Dynamic Response of Materials in the Aluminum Oxide–Aluminum Nitride Family

For armor applications, ceramic materials are often useful due to their high dynamic strength. In some instances, in addition to high strength, the armor must also be transparent, which significantly limits the choices of materials. Materials in the aluminum oxide–aluminum nitride family (including Al₂O₃ and AlON) are both strong and transparent. Only the end compound AlN is opaque. In this paper, the dynamic response to shock loading is examined for these materials to better understand the material response. Despite the chemical similarities, significant differences exist in the shock response and will be discussed.     

Diphonix® Resin: A Review of Its Properties and Applications

Abstract

The recently developed Diphonix® resin is a new multifunctional chelating ion exchange resin containing geminally substituted diphosphonic acid ligands chemically bonded to a styrene-based polymeric matrix. Diphonix can be regarded as a dual mechanism polymer, with a sulfonic acid cation exchange group allowing for rapid access, mostly non-specific, of ions into the polymeric network, and the diphosphonic acid group responsible for specificity (recognition) for a number of metal cations. The Diphonix resin exhibits an extraordinarily strong affinity for actinides, especially in the tetra- and hexavalent oxidation states. Therefore the resin has potential for applications in TRU and mixed waste treatment and characterization, and in the development of new procedures for rapid actinide preconcentration and separation from environmental samples. Metal uptake studies have been extended to alkaline earth cations, to transition and post-transition metal species, and to metal sorption from neutral or near neutral solutions. Also the kinetic behavior of the resin has been investigated in detail. In view of the above applications the influence of the most commonly occurring matrix constituents (Na, Ca, Al, Fe, hydrofluoric, sulfuric, oxalic and phosphoric acids) on the uptake of actinide ions has been measured. This review paper summarizes the most important results obtained in the studies on the properties of the Diphonix resin and gives an overview of the applications already in existence or under development in the fields of mixed waste treatment, actinide separation procedures, treatment of radwaste from nuclear power and fuel processing plants, and removal of iron from copper electrowinning solutions.