Hasil untuk "Chemical technology"

A. Dazzi, C. Prater

Zhong Lin Wang

Janusz J. Sikorski, Joy Haughton, M. Kraft

R. E. Kirk, D. Othmer

Luo Ming, Y. Yang, Shuzhong Wang et al.

Houqian Li, Horacio A. Aguirre-Villegas, R. D. Allen et al.

Less than 10% of the plastics generated globally are recycled, while the rest are incinerated, accumulated in landfills, or leach into the environment. New technologies are emerging to chemically recycle...

Subhajit Bhattacharjee, Stuart Linley, Erwin Reisner

Jingxin Shi, Wenping Huang, Hong-jun Han et al.

Abstract Reducing salt wastewater emissions to the outside world is significant for the “zero discharge” requirement of coal chemical industry. This review is mainly about the treatment technologies of salt-containing wastewater and high-salt wastewater in coal chemical industry of China. In the treatment of high-salt wastewater, coal chemical industry projects in China mostly use the “double membrane” reuse technology of “ultrafiltration + reverse osmosis”. Reverse osmosis is the core and main technology of reuse treatment, while ultrafiltration is the pretreatment and protection process. High-salt wastewater refers to the concentrated reverse osmosis wastewater of the reuse system. Evaporation crystallization technology can achieve “zero discharge” of wastewater by transforming high-salt wastewater into solid crystal mixed salt. It is a mature and recognized process at present stage, but the disposal of mixed salt is an urgent problem to be solved. Cooling crystallization and nanofiltration membrane can realize separation of mixed salt, but these technologies have not been applied to actual coal chemical project, and further research is needed.

Huan Liu, Guangji Hu, I. Basar et al.

Abstract Phosphorus (P) is a non-renewable resource, and its recovery and recycling are necessary for meeting future P demands and environmental conservation. Ash and hydrochar from incineration and hydrothermal liquefaction (HTL) of municipal sludge, respectively, represent promising sources for efficient P recovery. The full-scale application of wet-chemical techniques has proven their technical feasibility for P recovery from sludge-derived ash. HTL for sludge treatment has received significant attention for producing biocrude with net-positive energy recovery. P recovery from the solid by-product of sludge HTL, hydrochar, is a critical step in holistic sustainable sludge management. This review aims to guide P recovery from sludge-derived ash and hydrochar by presenting recent advances in wet-chemical extraction and precipitation. By comparing their characteristics, ash and hydrochar derived from municipal sludge exhibit similar feasibilities and challenges for P recovery. Extraction is recognized as the critical step for P recovery. The advantages and disadvantages of various P extraction approaches are provided. Acidic extraction achieves high efficiency (up to 100%) but requires removal of co-extracted heavy metals. Alkaline extraction prevents metals contamination but shows low efficiency (

Leah Buchman, Leah Buchman, Emma Kovak

Since the 1986 release of the Coordinated Framework for the Regulation of Biotechnology almost 40 years ago, there have been two whole of government updates that made only minor changes, while new regulations and guidance from individual agencies have made more substantial alterations. Despite scientific advances and the emergence of products that fall outside the purview of legacy statutes, repeated calls for substantive changes have gone largely unanswered. We expand upon the NSCEB’s most important recommendations for improvements to the Coordinated Framework. We recommend that Congress create an NBCO and direct it to create a centralized application submission portal; conduct horizon scanning for future products of biotechnology; streamline regulations for familiar products and exempt low-risk products; and improve organizational structure, staff training, and interagency exchange.

Katarzyna Grabowska, Łukasz Januszkiewicz, Ewelina Pabjańczyk-Wlazło

This study explores the electromagnetic properties of flat textile products enhanced with carbon nanotube (CNT) threads used as the weft. CNT threads, fabricated via dry-spinning, were integrated into fabrics by wrapping them around steel threads to form a solenoid-like structure. To further improve electromagnetic attenuation, the CNT yarn was coated with graphene oxide and silver nanoparticles. The research assessed the impact of these modifications on the fabric’s ability to attenuate alternating electromagnetic fields across a range of frequencies. Results showed enhanced attenuation at 30 MHz and 500 MHz. CNT yarn wrapped around steel threads achieved attenuation efficiencies of 18 dB at 30 MHz and 22 dB at 500 MHz, with a notable 10 dB improvement at 30 MHz over the reference. Fabrics with CNT yarn coated with graphene oxide demonstrated similar performance to the reference fabric at 500 MHz and an 8 dB increase at 30 MHz. Similarly, CNT yarn with silver nanoparticles showed comparable performance at higher frequencies but matched the reference at 30 MHz. These results indicate significant enhancement at lower frequencies, with benefits diminishing at higher. This study underscores the potential of integrating CNTs and metal nanoparticles into textiles to improve electromagnetic shielding, especially across specific frequencies.

Yusuke Kawamoto, You Wu, Yuki Takahashi et al.

Oligonucleotide-based therapeutics have attracted attention as an emerging modality that includes the modulation of genes and their binding proteins related to diseases, allowing us to take action on previously undruggable targets. Since the late 2010s, the number of oligonucleotide medicines approved for clinical uses has dramatically increased. Various chemistry-based technologies have been developed to improve the therapeutic properties of oligonucleotides, such as chemical modification, conjugation, and nanoparticle formation, which can increase nuclease resistance, enhance affinity and selectivity to target sites, suppress off-target effects, and improve pharmacokinetic properties. Similar strategies employing modified nucleobases and lipid nanoparticles have been used for developing coronavirus disease 2019 mRNA vaccines. In this review, we provide an overview of the development of chemistry-based technologies aimed at using nucleic acids for developing therapeutics over the past several decades, with a specific emphasis on the structural design and functionality of chemical modification strategies.

Anuj Joshi, Vedant Shah, P. Mohapatra et al.

Abstract The growth in the global energy consumption demands an increasing use of the renewable energy sources. Nevertheless, fossil fuels are projected to remain as the dominating backbone of petrochemical and consumer industry in the coming decades. As a bridge from the fossil fuel-based to renewable fuel-based economy, chemical looping technology has been developed to achieve sustainable applications by generating highly efficient energy and products through economically viable processes. This article discusses the advances in chemical looping with a focus on the fundamentals of formulation concepts on chemical looping carriers, rationale for reactor configurations, and design consideration from the process analysis. Particularly, the carriers utilized for different chemical looping applications ranging from syngas generation to ammonia synthesis are elaborated. The reactor configurations applied for different chemical looping systems are discussed along with the essentials of the process simulation approach to system optimization. The article also describes the prospects of the future development in the chemical looping technology, and its viability and readiness for industrial deployment.

Euiyeon Lee, Keshab Lal Shrestha, Seonhye Kang et al.

Epidermal growth factor (EGF)-mediated activation of EGF receptors (EGFRs) has become an important target in drug development due to the implication of EGFR-mediated cellular signaling in cancer development. While various in vitro approaches are developed for monitoring EGF-EGFR interactions, they have several limitations. Herein, we describe a live cell-based sensor system that can be used to monitor the interaction of EGF and EGFR as well as the subsequent signaling events. The design of the EGF-detecting sensor cells is based on the split-intein-mediated conditional protein trans-cleavage reaction (CPC). CPC is triggered by the presence of the target (EGF) to activate a signal peptide that translocates the fluorescent cargo to the target cellular location (mitochondria). The developed sensor cell demonstrated excellent sensitivity with a fast response time. It was also successfully used to detect an agonist and antagonist of EGFR (transforming growth factor-α and Cetuximab, respectively), demonstrating excellent specificity and capability of screening the analytes based on their function. The usage of sensor cells was then expanded from merely detecting the presence of target to monitoring the target-mediated signaling cascade, by exploiting previously developed Ca²⁺-detecting sensor cells. These sensor cells provide a useful platform for monitoring EGF-EGFR interaction, for screening EGFR effectors, and for studying downstream cellular signaling cascades.

Soonil Hong, Byoungwook Park, Chandran Balamurugan et al.

Efforts to commercialize organic solar cells (OSCs) by developing roll-to-roll compatible modules have encountered challenges in optimizing printing processes to attain laboratory-level performance in fully printable OSC architectures. In this study, we present efficient OSC modules fabricated solely through printing methods. We systematically evaluated the impact of processing solvents on the morphology of crucial layers, such as the hole transport, photoactive, and electron transport layers, applied using the doctor blade coating method, with a particular focus on processability. Notably, deposition of charge transport layer using printing techniques is still a challenging task, mainly due to the hydrophobic characteristic of the organic photoactive layer. To overcome this issue, we investigated the solvent effect of a well-studied cathode interlayer, bathocuproine (BCP). We were able to form a uniform thin BCP film (∼10 nm) on a non-fullerene based organic photoactive layer using the doctor bladed coating method. Our results showed that the use of volatile alcohols in the BCP processing required a delicate balance between wettability and vaporization, which contrasted with the results for spin-coated films. These findings provide important insights into improving the efficiency of printing techniques for depositing charge transport layers. The fully printed OSC modules, featuring uniform and continuous BCP layer formation, achieved an impressive power conversion efficiency of 10.8% with a total area of 10.0 cm2 and a geometrical fill factor of 86.5%.

Antonija Tomic, Marin Kovacic, Hrvoje Kusic et al.

Although heterogeneous photocatalysis has shown promising results in degradation of contaminants of emerging concern (CECs), the mechanistic implications related to structural diversity of chemicals, affecting oxidative (by HO•) or reductive (by O₂•⁻) degradation pathways are still scarce. In this study, the degradation extents and rates of selected organics in the absence and presence of common scavengers for reactive oxygen species (ROS) generated during photocatalytic treatment were determined. The obtained values were then brought into correlation as <i>K</i> coefficients (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>M</mi><mrow><mi>HO</mi><mo>•</mo></mrow></msub></mrow></semantics></math></inline-formula>/<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>M</mi><mrow><msub><mi mathvariant="normal">O</mi><mn>2</mn></msub><msup><mo>•</mo><mo>−</mo></msup></mrow></msub></mrow></semantics></math></inline-formula>), denoting the ratio of organics degraded by two occurring mechanisms: oxidation and reduction via HO• and O₂•⁻. The compounds possessing <i>K</i> >> 1 favor oxidative degradation over HO•, and vice versa for reductive degradation (i.e., if <i>K</i> << 1 compounds undergo reductive reactions driven by O₂•⁻). Such empirical values were brought into correlation with structural features of CECs, represented by molecular descriptors, employing a quantitative structure activity/property relationship (QSA/PR) modeling. The functional stability and predictive power of the resulting QSA/PR model was confirmed by internal and external cross-validation. The most influential descriptors were found to be the size of the molecule and presence/absence of particular molecular fragments such as C − O and C − Cl bonds; the latter favors HO•-driven reaction, while the former the reductive pathway. The developed QSA/PR models can be considered robust predictive tools for evaluating distribution between degradation mechanisms occurring in photocatalytic treatment.

Rachel M. Sumsion, Haylie M. June, Michael R. Cope

Rising rates of hunger and food insecurity have sparked a major re-evaluation of all aspects of food systems. Because of the multifaceted nature of food insecurity, however, determining what actions should be taken is challenging, especially since reevaluation efforts are led by experts from several disciplines and there is no consensus about which indicators should be used and how they should be measured. Confusion surrounding the meaning of the terms ‘food security’ and ‘food insecurity’ has contributed to this lack of consensus. As indicators inform action, such confusion has slowed those committed to alleviating hunger in identifying the most pressing targets. This review highlights (1) the importance of clearly defining food security and food insecurity and (2) how such definitions affect measures of food insecurity in the United States. While some might say that definitions are an issue of the past or a trivial matter of semantics, we believe that the world’s present rates of hunger and malnutrition are attributable, at least in part, to the lack of consensus on these definitions and their accompanying measurements and indicators. Although the present review can be helpful to academics and policy makers, the primary purpose is to be a resource to those involved in the day-to-day production of food, such as ranchers and farmers by providing an overview of definitions, indicators, and measurements used when discussing food security.

Nathália Leal Dominguez, Thaís Amaral Ferreira Baracho, Bruna de Abreu Toscano Souza et al.

Objetivo: Avaliar a relação do risco de síndrome de realimentação com desfechos clínicos (tempo de internação e óbito) em pacientes admitidos nos prontos socorros de dois hospitais públicos do Distrito Federal (DF). Método: Trata-se de um estudo com caráter longitudinal, prospectivo, observacional e analítico, o qual foi realizado em dois hospitais públicos do DF no período de agosto de 2018 a agosto de 2019. Resultados: A amostra foi composta por 478 pacientes admitidos nos prontos-socorros dos dois hospitais. Observou-se que 45,60% da amostra apresentou risco nutricional e 32,22% algum grau de desnutrição. A frequência do risco para síndrome de realimentação foi de 23,65%. Os pacientes que apresentaram risco para síndrome de realimentação apresentaram 83% mais risco de permanecerem internados por mais de 7 dias e 58% mais risco de óbito em relação aos pacientes que não apresentaram risco para SR. Conclusão: Pacientes que apresentam risco para síndrome de realimentação permaneceram mais tempo internados e possuem mais risco de irem a óbito.

Yun-a Kim, Sanghun Park, Yunhwan Park et al.

This study aimed to determine whether fermented soy sauce has a mutually synergistic effect on the quality and storage properties of pork patties, and to investigate the effects on the availability and physicochemical properties of various taste ingredients of soy sauce, a traditional Korean food ingredient. The experimental groups were as follows: Control (−): No additives; Control (+): 0.1% ascorbic acid; T1: 1% fermented soy sauce; T2: 3% fermented soy sauce; T3: 5% fermented soy sauce. No significant difference was detected in moisture, protein, and fat among the various treatment groups; however, ash content and water holding capacity increased and texture properties improved with the concentration of fermented soy sauce. The addition of fermented soy sauce during refrigerated storage for 10 days showed a positive effect on the storage properties. The peroxide value, content of thiobarbituric acid reactive substances and total phenolics, and 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity differed significantly in pork patties with different treatments and storage intervals. The effect of fermented soy sauce on the overall quality and storage properties of pork patties during refrigerated storage is relatively unknown. These findings demonstrate that the addition of fermented soy sauce improves the quality properties and antioxidant activity of pork patties.

Johannes Wunderlich, Katy Armstrong, G. Buchner et al.

Abstract Both an environmental and an economic assessment are needed to judge the potential of sustainable chemical technologies. However, decision-makers may be challenged by conflicting conclusions. The integration of life cycle assessment (LCA) and techno-economic assessment (TEA) can enhance decision-making, as integrated assessments provide more information than a simple reporting of separate TEA and LCA results. The analysis of integration approaches reveals a lack of consistency in terms of defining criteria and methodological aspects for integration. A gap remains where guidance for practitioners is needed on how to select a suitable integration type for their different purposes. To fill this gap, we conclude that a one-size-fits-all solution of integration cannot adequately serve all purposes along the technology development phases. Therefore, a framework to guide through integration in three distinct parts is proposed. In Part I, a four-phase approach for every integrated assessment to link the results from TEA and LCA is defined. Part II develops three integration types classified by their core characteristics: qualitative discussion-based (Type A), quantitative combined indicator-based (Type B), and quantitative preferences-based (Type C). Finally, in Part III, a step-by-step method to select the appropriate integration type according to the assessment purpose, while considering restrictions imposed by technology maturity and resource availability is introduced. Thus, the framework is a basis for increasing the number of integrated assessments by guiding practitioners towards tailored studies.