Developing a molecular platform for potential carbon dioxide fixing

This paper presents an attempt to develop a new system for fixing carbon dioxide from the atmosphere. The proposed molecular system has been designed to have the capacity to spontaneously bind CO₂ from the atmosphere with high affinity. The molecular system is furthermore designed to have the ability to liberate CO₂ at a later stage in the process, i.e., in a separate compartment. The liberated CO₂ presents a carbon neutral way of obtaining pure CO₂. The proposed molecular system is based on a small stable organic molecule that potentially have two forms: one without bound CO₂ and one with bound CO₂. One class of molecules that undergo a reaction compatible with our purposal is the merocyanine dyes that exhibit photochromic properties. Based on this structural class of molecules, a system for the potential fixing of CO₂ has been developed.     

Combinatorial chemistry methods for coating development: VI. Correlation of high throughput screening methods with conventional measurement techniques

Combinatorial chemistry has proven to be a valuable tool for the development of new compounds. In the pharmaceutical industry, where combinatorial chemistry began, the approach has been instrumental in the high-speed development of new drugs. Due to the overwhelming success of the combinatorial methodology in the pharmaceutical industry, it has been recently applied to materials development. We have recently developed a combinatorial factory capable of preparing and evaluating on the order of 100 organic clear coatings in a day.

One of the most challenging aspects of the creation of the combinatorial factory was the development of the high throughput screening (HTS) methods for the primary coating properties of interest such as optical clarity, abrasion resistance, adhesion, and weatherability. For each property, an entirely new method was developed that allowed for rapid measurement of these properties on very small samples. This paper describes various aspects of the development of these novel measurement systems including the correlation of the HTS methods with conventional, industry standard measurement methods.     

Development of construction materials using sulfite-rich scrubber sludge and fly ash

Construction materials with characteristics suitable for a variety of applications have been developed using up to 95% of coal combustion by-products comprising of sulfite-rich scrubber sludge and fly ash. These materials can be produced as soil-like mixes that can be prepared at the power plant, transported to the deployment site and compacted using conventional road building equipment without a need for forms. These developed materials provide an early strength of 5.8-8.3 MPa after 7-14 d and are environmentally benign. For a cattle feeding pad application, which is the focus of this paper, the cost is estimated be about 25-30% of the cost of developing a conventional concrete feeding pad. Following mix development and establishment of quality assurance/quality control protocols, a commercial cattle feeding pad has been designed and demonstrated using the developed mix.     

High-performance poly(butylene oxide)/poly (ethylene oxide) block copolymer surfactants for the preparation of water-in-oil high internal phase emulsions

High-performance surfactants have been developed for the preparation of water-in-oil high internal phase emulsions (HIPE), particularly for the preparation of polymerized HIPE foams. High-efficiency surfactants with poly(butylene oxide)/poly(ethylene oxide) (BO/EO) block copolymer backbones have been developed that can stabilize an HIPE through polymerization at concentrations as low as 0.006 wt% based on total emulsion weight. Polymerizable versions have been developed that bind into the polymeric foam backbone. BO/EO block copolymer surfactants also allow preparation of polymerized HIPE foams without salt in the aqueous phase. HIPE with the BO/EO surfactants have been prepared at room temperature and polymerized at temperatures exceeding 90°C. By minimizing the required amount of surfactant, allowing the surfactant to react during HIPE polymerizations, eliminating the need for salt, and stabilizing over a broad range of temperatures, BO/EO block copolymer surfactants have demonstrated their place as high-performance HIPE surfactants.     

Computational Chemistry in the Pharmaceutical Industry: From Childhood to Adolescence

Computational chemistry within the pharmaceutical industry has grown into a field that proactively contributes to many aspects of drug design, including target selection and lead identification and optimization. While methodological advancements have been key to this development, organizational developments have been crucial to our success as well. In particular, the interaction between computational and medicinal chemistry and the integration of computational chemistry into the entire drug discovery process have been invaluable. Over the past ten years we have shaped and developed a highly efficient computational chemistry group for small‐molecule drug discovery at Bayer HealthCare that has significantly impacted the clinical development pipeline. In this article we describe the setup and tasks of the computational group and discuss external collaborations. We explain what we have found to be the most valuable and productive methods and discuss future directions for computational chemistry method development. We share this information with the hope of igniting interesting discussions around this topic.     

Fluorescent probes and functional materials for biomedical applications

Due to their simplicity in preparation, sensitivity and selectivity, fluorescent probes have become the analytical tool of choice in a wide range of research and industrial fields, facilitating the rapid detection of chemical substances of interest as well as the study of important physiological and pathological processes at the cellular level. In addition, many long-wavelength fluorescent probes developed have also proven applicable for in vivo biomedical applications including fluorescence-guided disease diagnosis and theranostics (e.g., fluorogenic prodrugs). Impressive progresses have been made in the development of sensing agents and materials for the detection of ions, organic small molecules, and biomacromolecules including enzymes, DNAs/RNAs, lipids, and carbohydrates that play crucial roles in biological and disease-relevant events. Here, we highlight examples of fluorescent probes and functional materials for biological applications selected from the special issues “Fluorescent Probes” and “Molecular Sensors and Logic Gates” recently published in this journal, offering insights into the future development of powerful fluorescence-based chemical tools for basic biological studies and clinical translation.     

Membrane‐Active Small Molecules: Designs Inspired by Antimicrobial Peptides

Infectious diseases continue to be one of the major contributors to human morbidity. The rapid rate at which pathogenic microorganisms have developed resistance against frontline antimicrobials has compelled scientists to look for new alternatives. Given their vast antimicrobial repertoire, substantial research effort has been dedicated toward the development of antimicrobial peptides (AMPs) as alternative drugs. However, inherent limitations of AMPs have driven substantial efforts worldwide to develop synthetic mimics of AMPs. This review focuses on the progress that has been made toward the development of small molecules that emulate the properties of AMPs, both in terms of design and biological activity. Herein we provide an extensive discussion of the structural features of various designs and we examine biological properties that have been exploited. Furthermore, we raise a number of questions for which the field has yet to provide solutions and discuss possible future research directions that remain either unexploited or underexploited.     

Momentum/heat transfer analogy for drag reducing fluids during turbulent boundary layer flow with small pressure gradients

There have been many attempts in the literature to develop analogies for momentum, heat and mass transfer to drag reducing fluids; however, none have considered the presence of a pressure gradient when formulating the analogies. In the present work, a momentum/heat transfer analogy has been developed under the influence of small pressure gradient for drag reducing fluids using the Nakayama et al. (1984) solution methodology for Newtonian fluids. The results of the present analysis have been found to compare well with existing theoretical expressions.     

Phyto-synthesized silver nanoparticles for biological applications

Silver nanoparticles (AgNPs) are valuable metal nanoparticles that exhibit exceptional properties compared to their bulk materials. Pronounced surface area, quantum confinement effect complemented by small particle dimension, and many other extraordinary characteristics make AgNPs suitable in a variety of applications. Different methods have been adopted to synthesize AgNPs. Biological methods can formulate AgNPs in an environmentally friendly manner without producing toxic waste. Among the biological methods, plants are simple and attractive sources for AgNP synthesis. Compared to AgNPs produced via other modes of synthesis, phyto-synthesized AgNPs, due to their safety features, have been found to be advantageous for a variety of applications, especially biological applications. Strong research efforts have investigated the utility of phyto-synthesized AgNPs for different applications. Investigators are coming up with innovative applications of phyto-synthesized AgNPs for the development of science and technology and to benefit humankind. The present article focuses on phyto-synthesized AgNPs for biological applications, with a brief review of their synthesis, mechanism, and size/shape control.     

The Mechanism of Filler Reinforcement from addition of neutral polymeric bonding agents to energetic polar propellants

It has been demonstrated that addition of small amounts of the newly developed neutral polymeric bonding agents (NPBA's) to energetic propellants such as HMX/PEG/NG composites causes strong filler reinforcement. The mechanism of this reinforcement occurs through interfacial effects, and not because of an overall increase in the crosslink density of the binder. It has been demonstrated directly that the NPBA's have a favorable relative affinity for HMX and concentrate at the solid surface during mixing. All the experimental evidence supports the theory that highly crosslinked polymeric shells form around the HMX particles and chemically bond to the binder matrix during the cure, thus causing an increase in the initial modulus. Furthermore, these shells appear to eliminate the weak, soft layers around the particles, and hence filler reinforcement persists up to much higher elongation than without addition of NPBA. Based on the filler reinforcement observed, the simple one-step procedure of incorporating our NPBA is almost as effective as the more costly process of precoating the particles.     

Targeted Small-Molecule Conjugates: The Future is Now

In recent years, novel classes of small hetero-bifunctional compounds have been developed as tools for the treatment of cancer and other diseases through different approaches, from radio/chemotherapy and imaging to immunotherapy and protein degradation. Within this growing research area, progresses in ligand-screening procedures and hit-to-lead optimizations, together with advances in drug-release technologies, are paving the way to the future treatment of a broad range of pathologies with small targeted therapeutics.     

管式反应器在化肥工业中的应用与研究进展

管式反应器在近 40年里 ,由于其体积小、效率高的特点 ,在化肥工业中的应用与发展十分迅速。我国自 2 0世纪 80年代引进这一先进技术后 ,一些研究、设计院和高校大力协同 ,积极开展基础研究工作和承担工程项目 ,至今取得了很大的成绩 ,填补了这一领域的空白。随着现代高科技的迅猛发展 ,我国研制的新型管式反应器也必将赶上世界先进水平     

Effect of Outer Surface Sealing Treatment on the Reduction of Surface Check Occurrence During the Drying of Center-Bored Round Timber

A significant amount of time and energy is required to dry green timber with a large cross-section. Due to long-lasting internal moisture gradients, internal stress is high during the drying of large cross-sectional timber, and the potential for check occurrence is significant. Although many researchers have aimed to develop a method for drying large pieces of wood without the occurrence of drying defects, a procedure for rapidly drying wood without cracks has not yet been developed. In the present study, an outer surface sealing method and center-boring process (i.e., drilling a hole along the central longitudinal axis) was developed to dry timber with a large cross-section without the occurrence of checks. The proposed center-boring procedure reduces the movement of heat and moisture inside the wood and expedites the drying process by sustaining a small MC gradient. Moreover, the outer surface sealing treatment changes the drying stress direction and controls check occurrence. By kiln drying center-bored (80-mm diameter) and outer-surface-sealed round timber pitch pine (Pinus rigida) with an initial MC of 30% and an outer diameter of 140 mm, a final MC of 6% was obtained within 40 hours without the occurrence of any drying defects.     

The oxidative coupling of methane on alkali- and alkaline earth-phosphate catalysts

The oxidative coupling of methane has been tested over alkali- and alkaline earth-phosphate catalysts at 700 and 775 °C with and without the introduction of a small quantity of tetrachloromethane (TCM) to the feedstream. In general, the conversion of methane was enhanced by the addition of TCM but the effect on selectivity was dependent on the catalyst being examined. The selectivity to C₂ and higher hydrocarbons and that to oxidation products have been shown to have a dependence on the cation radius/charge ratio.     

Pilot-plant process for starch xanthide encapsulated pesticides

A small pilot-plant batch process for the encapsulation of pesticides with crosslinked starch xanthate (starch xanthide) has been developed. Multipound quantities of several encapsulated pesticides have been prepared that have slow-release properties. Products were made from starch xanthates of varying degrees of substitution (0.1 to 0.3) and with various crosslinking agents (H₂O₂, NaNO₂, NaOCl, NaClO₂, and FeCl₃). Recovery of the pesticides as the encapsulated product ranged from 62% to nearly 100%. In a single experiment, processing water was recycled without apparent problems.     

Cellular engineering for the high-level production of recombinant proteins in mammalian cell systems

The market for protein-drugs has steadily increased due their increased use as alternatives to traditional small molecule drugs. While some therapeutic proteins have been produced in microbial systems, mammalian cell systems such as Chinese hamster ovary (CHO) cells are widely used as the host cell system. To increase the efficiency of producing therapeutic proteins, many researchers have attempted to solve the critical problems that occur in mammalian cell systems. As a result, several serum-free media and advanced culture methods have been developed, and protein productivity has increased considerably through the development of efficient selection methods. However, the prevalence of apoptosis during mammalian cell culture still remains a significant problem. Based on the understanding of apoptotic mechanisms and related proteins, anti-apoptotic engineering has steadily progressed. In this study, we review the strategies that have been developed for high-level production of recombinant proteins in the CHO cell system via a selection of clones, target-gene amplification, optimization of culture systems and an inhibition of apoptosis through genetic modification.     

The determination of doubly labeled artificial soil in detergency studies

A liquid scintillation method for the determination of carbon-14 and tritium labeled soil on white fabric has been developed. The method involves the use of an external standard to determine the counting efficiency for each isotope. The requirement that these determinations be made on swatches of fabric complicates the analysis because of their variable antiquenching effect. The method has been appied to cotton, Dacron, nylon, and Dacron/cotton. A computer program has been written which accepts the raw counting data and performs all necessary calculations, printing out the data in a convenient form. The great convenience of the method has encouraged its application to large scale screening studies without sacrificing the precision, accuracy, or selectivity normally associated with small model systems.     

The mixing effect on the free radical MMA solution polymerization

Mathematical models of reactors for the polymerization of methylmethacrylate (MMA) have been developed and analyzed to elucidate reactor dynamics and to determine conditions for improved operation. The effects of mixing and heat transfer in an MMA polymerization reactor system have been explored by the development of an imperfect mixing model. To model imperfect mixing in polymerization, a reactor configuration using two tanks in parallel was used. Bifurcation diagrams developed using numerical analysis of the model have been drawn with two variable parameters, an exchange ratio, σ, and a volume ratio, κ. We use feed and coolant temperatures as bifurcation parameters. If variable parameters are small, the lower solution branch of the steady state solutions is quite different from that of a simple model that assumes perfect macro-mixing as bifurcation parameters change. If σ increases (κ=0.1, σ=1.0), the shape of a steady state solution curve differs significantly from that of a simple model as the feed temperature decreases.