Unwanted By-products Research Articles

Human oncoprotein 5MP suppresses general and repeat-associated non-AUG translation via eIF3 by a common mechanism.

eIF5-mimic protein (5MP) is a translational regulatory protein that binds the small ribosomal subunit and modulates its activity. 5MP is proposed to reprogram non-AUG translation rates for oncogenes in cancer, but its role in controlling non-AUG initiated synthesis of deleterious repeat-peptide products, such as FMRpolyG observed in fragile-X-associated tremor ataxia syndrome (FXTAS), is unknown. Here, we show that 5MP can suppress both general and repeat-associated non-AUG (RAN) translation by a common mechanism in a manner dependent on its interaction with eIF3. Essentially, 5MP displaces eIF5 through the eIF3c subunit within the preinitiation complex (PIC), thereby increasing the accuracy of initiation. In Drosophila, 5MP/Kra represses neuronal toxicity and enhances the lifespan in an FXTAS disease model. These results implicate 5MP in protecting cells from unwanted byproducts of non-AUG translation in neurodegeneration.

Fluoride-rich wastewater treatment by ballast-assisted precipitation with the selection of precipitants and discarded or recovered materials as ballast

Fluoride is commonly an unwanted by-product in industrial processes becoming highly concentrated at the effluent reaching 1,000 to 50,000 ppm F–. However, most of the defluoridation studies focused on the treatment of low concentrations of fluoride <100 ppm. Thus, traditional precipitation-coagulation by calcium was previously utilized to efficiently defluoridate very high initial concentrations. However, it produced non-settleable solids at initial concentrations between 500 and 5,000 ppm F–. To overcome these drawbacks, the ballast-precipitation was simulated under laboratory scale with a volume of 500-mL containing synthetic wastewater (4,000 ppm F–). The preliminary investigations focused on the comparison of different precipitants previously reported (Al, Ca, Mg, Zr, and Fe). Moreover, the recovered materials from wastewater treatment (CaCO3 and CaHPO4) and discarded industrial solid waste (Al2O3, FeOOH, and SiO2) have been investigated as potential ballast. Optimum defluoridation using different precipitants was also found at different pH. The results showed that Ca remained the most feasible precipitant with the highest defluoridation efficiency (Ca > Fe > Al > Zr > Mg). Meanwhile, among the discarded and recovered materials use for ballast CaCO3 demonstrated the highest defluoridation efficiency (CaCO3 > Al2O3 > CaHPO4 > SiO2 > Fe2O3). Calcite did not only act as ballast but also a precipitant by providing additional calcium ions through leaching. The defluoridation by ballasted precipitation could efficiently remove fluoride by 99% and reduced turbidity >90%. Moreover, the parameter correlation could be fitted in a quadratic equation (r2 from 0.8763 to 0.9999). The coefficients were used to estimate the significance of each parameter (showing pH > Ca/2F ratio > ballast dosage).

One-Pass Conversion of Benzene and Syngas to Alkylbenzenes by Cu-ZnO-Al2O3 and ZSM-5 Relay.

Alkylbenzenes have a wide range of uses and are the most demanded aromatic chemicals. The finite petroleum resources compels the development of production of alkylbenzenes by non-petroleum routes. One-pass selective conversion of benzene and syngas to alkylbenzenes is a promising alternative coal chemical engineering route, yet it still faces challenge to industrialized applications owing to low conversion of benzene and syngas. Here we presented a Cu–ZnO–Al2O3/ZSM-5 bifunctional catalyst which realizes one-pass conversion of benzene and syngas to alkylbenzenes with high efficiency. This bifunctional catalyst exhibited high benzene conversion (benzene conversion of 50.7%), CO conversion (CO conversion of 55.0%) and C7&C8 aromatics total yield (C7&C8 total yield of 45.0%). Characterizations and catalytic performance evaluations revealed that ZSM-5 with well-regulated acidity, as a vital part of this Cu–ZnO–Al2O3/ZSM-5 bifunctional catalyst, substantially contributed to its performance for the alkylbenzenes one-pass synthesis from benzene and syngas due to depress methanol-to-olefins (MTO) reaction. Furthermore, matching of the mass ratio of two active components in the dual-function catalyst and the temperature of methanol synthesis with benzene alkylation reactions can effectively depress the formation of unwanted by-products and guarantee the high performance of tandem reactions.Graphic Supplementary InformationThe online version contains supplementary material available at 10.1007/s10562-021-03617-5.

Formation of Formaldehyde and Other Byproducts by TiO2 Photocatalyst Materials

Photocatalysts promised to control pollution in an environmentally benign manner, inexpensively, and with a low or cheap energy input. However, the limited chemical activity of photocatalysts has prevented their widespread use. This limitation has two important consequences; in addition to limited removal efficiency for pollution, photocatalysts may also generate unwanted byproducts due to incomplete reaction. This study focuses on the byproducts formed in the photocatalytic degradation of dimethyl sulfide (DMS) on titanium dioxide (TiO2), using a continuous flow reactor and detection via proton transfer reaction mass spectrometry. TiO2, activated carbon (AC), TiO2/AC (1:1) and TiO2/AC (1:5) were tested using either a laser-driven light source or LED lamps at 365 nm. The samples were characterized using a N2-BET surface area and pore size distributions, Scanning Electron Microscopy, X-ray Diffraction, and X-ray Photoelectron Spectroscopy, which confirmed that TiO2 was successfully coated on activated carbon without unexpected phases. TiO2 and activated carbon showed different removal mechanisms for DMS. The maximum yield of formaldehyde, 11.4%, was observed for DMS reacting on a TiO2/AC (1:5) composite operating at a DMS removal efficiency of 31.7% at 50 ∘C. In addition to formaldehdye, significant products included acetone and dimethyl disulfide. In all, observed byproducts accounted for over half of the DMS material removed from the airstream. The TiO2/AC (1:5) and TiO2/AC (1:1) composites have a lower removal efficiency than TiO2, but a higher yield of byproducts. Experiments conducted from 20 ∘C to 70 ∘C showed that as temperature increases, the removal efficiency decreases and the production of byproducts increases even more. This is attributed both to decreased surface activity at high temperatures due to increased recombination of reactive species, and to the decreased residence time of volatile compounds on a hot surface. This study shows that potentially dangerous byproducts are formed by photocatalytic reactors because the reaction is incomplete under the conditions generally employed.

Epoxidation of trans-stilbene in a microfluidic plasma reactor

Novel organic synthesis routes that circumvent the need for a catalyst and reduce unwanted by-products are highly sought by industry. A novel microfluidic plasma reactor that generates a dielectric barrier discharge (DBD) plasma in the vicinity of the gas-liquid interface and facilitate a chemical reaction at the interface of microbubbles has been used for trans-stilbene epoxidation. Three different operating strategies were implemented to optimise the transfer of species selectivity: single pass, multi-pass and continuous recirculation. The effect of initial trans-stilbene concentration, oxygen content in the feed gas mixture and reaction time on the epoxide formation was studied to optimise the chemical reaction. The optimum operating conditions were found to be short bubble-liquid contact times (~2 s) with frequent exposure to freshly generated microbubbles containing reactive species by continuous liquid recirculation, and under these conditions the overall epoxide yield was ~94% with an overall epoxide selectivity of 10:1.

Dissolved organic carbon removal and CX3R-type byproduct formation during the peroxymonosulfate pre-oxidation followed by coagulation

Hydroxyl radicals (HO·) and sulfate radicals (SO4−) can be generated when ferric-based coagulants are coupled with the potential alternative pre-oxidant peroxymonosulfate (PMS). Although HO·, SO4− and PMS may oxidize most organic matter, they could also react with chloride stemming from chloride-containing coagulants, generating reactive chlorine species that may further react with organic matter to produce unwanted byproducts. CX3R-type [X = H or Cl, R = H, CN, C(OH)2 or CONH2] byproducts have cytotoxicity and genotoxicity. Therefore, the dissolved organic carbon (DOC) removal and CX3R-type byproduct formation during the PMS pre-oxidation followed by coagulation (PPFC) (ferric sulfate [Fe2(SO4)3], ferric chloride (FeCl3), aluminium sulfate [Al2(SO4)3] or aluminium chloride (AlCl3)) were investigated. Results showed that PPFC could remove DOC higher compared to PMS pre-oxidation or coagulation alone. The DOC removal efficiency followed the order of Fe2(SO4)3 > FeCl3 > Al2(SO4)3 > AlCl3 during the PPFC. During the PPFC, FeCl3 and AlCl3 resulted in the formation of CX3R-type byproduct that posed significant calculated toxicity induction, while Fe2(SO4)3 and Al2(SO4)3 did not. Compared to AlCl3, FeCl3 resulted in higher CX3R-type byproduct concentration and finished water toxicity, which both decreased as the pre-oxidation duration extended, and increased as the PMS concentration increased. The CX3R-type byproduct formation and finished water toxicity increased and then decreased as both sedimentation time and coagulant dosage increased. Compared to PMS and SO4−, HO· played a more significant role in the formation of CX3R-type byproduct and induction of toxicity of finished water during the PPFC (FeCl3). Therefore, Fe2(SO4)3 was the more suitable coagulant when PMS was used as the pre-oxidant.

Effect of the contact tank geometry on disinfection efficiency

Disinfection is a sanitary treatment present in both drinking water and wastewater treatment plants aimed at removing pathogenic microorganisms able to damage the human health. The focus of this study is to apply Computational Fluid Dynamics (CFD) to study and to improve the disinfection efficiency through the optimization of the hydrodynamics inside the disinfection tank. Numerous literature studies have shown that water flow inside traditional multichamber tanks is highly turbulent because of the development of large as well as small vortices in which flow velocity decreases or even vanishes (dead zones). These turbulent phenomena are responsible of an increase of the real residence time, compared to the theoretical one, causing poor disinfection and the development of unwanted by-products. In the present analysis, Large Eddy Simulation (LES) is used to simulate three-dimensional turbulent flow and disinfectant transport in different contact tanks using a structured finite-volume discretization. The results show how the baffles’ geometry, as well as the design of technical and construction details, influences the hydraulic retention time of the disinfectant, varying the disinfection efficiency. In particular, the creation of horizontal baffles inside the vertical baffle chambers reduces the free space and extends the flow path. This reduces both short circuits and recirculation zones bringing the flow closer to the ideal plug-flow condition.

Electrochemical Utilization of CO2 From Coal Power Plants

The conversion of CO2 to value-added products is an attractive approach for reducing the cost of CO2 capture. The successful development of a commercially viable process to convert post-combustion CO2 into formic acid will have a multitude of benefits to the CO2 capture community by partially offsetting the cost of carbon capture from the utility and industrial sectors. The deployment of CO2 utilization technologies will result in two major benefits: 1) reducing the cost of CO2 capture from coal-fired utility units; and 2) production of a valuable product, formic acid, at a lower cost than is currently available. Formic acid is a multipurpose industrial chemical feedstock for formic acid fuel cells, additives in the textile and agricultural sectors, cleaning products, and corrosion inhibitors. The state-of-the-art Kemira process for industrial formic acid production is energy-intensive and requires additional separation and purification steps to produce purified formic acid. Conversely, an electrochemical approach reduces the chemical input for formic acid production, and can be produced directly with electricity supplied via renewable/intermittent power sources. However, conventional electrochemical processes for CO2 reduction to formic acid exhibit selectivity issues where the electro-catalyst typically produces unwanted by-products like hydrogen, carbon monoxide, methanol, and methane that reduces the faradaic efficiency of the CO2 conversion process by up to 50%. To overcome current efficiency difficulties, a process has been developed featuring a catalyst with high selectivity for formic acid production (+90% conversion efficiency). The CAER-Andora process combines an electrochemical cell that features graphite electrodes and an electrochemically facile charge mediator, combined with an immobilized proprietary catalyst. These processes work together to 1) reduce faradaic inefficiencies by producing only formic acid, 2) protect the valuable catalyst from deactivation by overpotentials.

Cesium-free pair-plasma creation method may aid future fusion experiments

Aluminum can replace cesium-coated metal grids for the creation of pair-plasmas, with higher density and less unwanted byproducts.

From Ta2S5 Wires to Ta2O5 and Ta2O5-x S x.

Synthesis routes to forming novel materials are oftentimes complicated and indirect. For example, Ta2S5 has only been found as an unwanted byproduct of certain chemical reactions, and its properties were unknown. However, here we demonstrate the growth of Ta2S5 wires with steel-like tensile strength, which are also precursors for the first controlled synthesis of long, mesoscopic Ta2O5 wires and superconducting Ta2O5–xSx wires. Single-crystal wires of tantalum pentasulfide, Ta2S5, were first grown using vapor transport from polycrystalline XTa2S5, sulfur, and TeCl4 in fused-quartz tubes, where X = Ba or Sr. Crystals form as long wires with lengths on the order of a few centimeters and varying cross sections as small as 25 μm2. They were found to have steel-like tensile strength, and their crystal structure was determined using X-ray diffraction to be monoclinic with space group P2/m and with lattice parameters a = 9.91(7) Å, b = 3.82(5) Å, and c = 20.92(2) Å. Electrical resistivity measurements reveal Ta2S5 to be a narrow band gap semiconductor with Eg = 110 meV, while a Debye temperature ΘD = 97.0(5) K is observed in specific heat. Tantalum pentasulfide wires were then converted to insulating tantalum pentoxide (Ta2O5) wires after calcinating them for 30 min in air at 900 °C. Finally, tantalum pentoxide wires were converted to tantalum oxysulfide (Ta2O5–xSx) wires after annealing them in CS2 vapor for 30 min at 900 °C. The oxysulfide crystal structure was determined using X-ray diffraction to be that of β-Ta2O5. Electrical and magnetic measurements reveal Ta2O5–xSx to be metallic and superconducting with Tc = 3 K.

Capitalism, contradictions, crises: pushing back the limits to capital or breaching the capacity of the planetary ecosystem?

ABSTRACT Capitalist economies are structured around two fundamental contradictions. The first lies within the social relations of capital, and the second in the ‘metabolic rift’ between capital accumulation and nature. While the adverse effects of the first do create systemic existential crises, capital and its political representatives have discovered ways of temporarily containing them and creating new space for enhanced accumulation. In contrast, the risks emanating from the second contradiction, located in the disjuncture between capital’s need for compound economic growth and the capacity of the planetary ecosystem as a source of material inputs and a sink for inevitable unwanted by-products, cannot be so contained. As such, the second contradiction represents an immanent existential threat to the capitalist mode of production and the societies in which it is, to varying degrees, embedded, of which the most pressing contemporary expression is enhanced global warming.

Human Oncoprotein 5MP Suppresses General and Repeat-Associated Non-AUG Translation Via eIF3 by a Common Mechanism

eIF5-mimic protein (5MP) is a translational regulatory protein that binds the small ribosomal subunit and modulates its activity. 5MP is proposed to reprogram non-AUG translation rates for oncogenes in cancer, but its role in controlling non-AUG initiated synthesis of deleterious repeat-peptide products, such as FMRpolyG observed in Fragile-X associated tremor ataxia syndrome (FXTAS), is unknown. Here we show that 5MP can suppress both general and repeat-associated non-AUG (RAN) translation by a common mechanism in a manner dependent on its interaction with eIF3. Essentially, 5MP1 assures stoichiometric and ordered interaction of eIF3c within the PIC, thereby increasing the accuracy of initiation. In Drosophila, 5MP/Kra represses neuronal toxicity and enhances lifespan in a FXTAS disease model. These results implicate 5MP in protecting cells from unwanted byproducts of non-AUG translation in neurodegeneration.

Conversion of chromium-containing solid wastes into value-added products through a plasma-assisted aluminothermic process.

Chromium-containing solid wastes have been generated by chemical and leather/tanning industries, and the management and proper disposal of the same wastes have been challenging tasks. A significant fraction of these wastes contains chromium compounds with chromium present in the hexavalent (Cr+6) form, which is hazardous to human beings, animals, and ecosystems. Since these wastes are discarded largely without proper treatments, soil and groundwater get contaminated and they can cause several health issues to human beings. Conventional methods developed to convert hazardous Cr6+ to Cr3+/Cr metal either generate secondary toxic wastes and unwanted by-products and/or are time-consuming processes. In this work, a plasma-assisted aluminothermic process is developed to convert the toxic waste into non-toxic products. The waste was mixed with aluminium powder and subjected to transferred arc plasma treatment in a controlled air atmosphere. Chemical analysis and Cr leachability studies of the waste material prior to plasma treatment have shown that it is highly toxic. Analysis of the products obtained from the plasma treatment showed that Cr and Fe present in the waste could be recovered as a metallic mixture as well as oxide slag, which were found to be non-toxic. Easy separation of the metallic fraction and the slag from the treated product is one of the merits of this process. Besides converting chromium-containing toxic waste to non-toxic materials, the process is rapid and recovers the metals from the waste completely.

Technology for Treating Oily Wastewater Derived from Various Industries: A Review Paper

The increasing number of industrial sectors has resulted in more and more contaminated water and wastewater containing various harmful pollutants including oil compounds. Less treated or untreated oily wastewater could give a serious threat to both human health and environmental sustainability. Therefore, the appropriate treatment methods such as membrane filtration, coagulation/flocculation, biological treatment, adsorption, and relevant integrated methods have to be implemented well to enhance the quality of those wastewaters before they flow into the final disposal place. This effort will endorse the success of waste management and circular economy system by recycling unwanted industrial by-products including wastewater, so it can be reused for further productive purposes.

Effect of recycled fine aggregates on alkali-activated slag concrete properties

Normally, recycled fine aggregate (RFA) is an unwanted by-product of construction demolished waste crushing, with high contaminant content. The presence of RFA is highly restricted in ordinary Portland cement (OPC) concrete production because of the poor durability and mechanical performance. This paper presents a study of the effect of RFA on the mechanical and durability of alkali activated slag concrete (AASC). Results indicated that RFA can be used as fine aggregate in AASC with superior early age compressive strength compared to river sand in AASC. It is caused by the presence of non-hydrated cement paste attached to the RFA with alkali activate property, which is equivalent to increase the quantity of alkali activator, and accelerate the hydration of ground granulated blast furnace slag (GGBFS) especially in the early age. In later age, the mechanical properties of AASC incorporating RFA are slightly lower than conventional AASC due to the larger porosity in the concrete.

Mechanochemystry as advanced methodology in green chemistry for applied catalysis

In this survey we have assessed how mechanochemistry techniques comply with the aims of Green Chemistry to minimise the use of environmentally damaging reactants and unwanted by-products. In the publications the preparation of vanadium-phosphorus oxides as industrial catalysts for maleic anhydride production from n-butane and perspective catalysts of phthalic anhydride manufacture by direct n-pentane oxidation were analyzed. It is shown that mechanochemical activation and synthesis reduces the amount of harmful waste used in the production of the catalyst and increases its effectiveness. Improvement of a catalyst’s properties, help limit production of harmful emissions such as carbon oxides and hydrocarbons. It was established that mechanochemical treatment can by successfully used in the process of industrial vanadium-phosphorus oxide catalysts modification or in the process of introduction in its composition of additives which lead to increase of activity and selectivity of hydrocarbons oxidation. The possibility of the mechanochemistry use in the vanadium-titanium oxide catalysts preparation which are the base catalysts in industrial phthalic anhydride production from o-xylene was determined. It was established that mechanochemical treatment of the vanadium and titanium oxides mixture permits to delete the nitrogen oxides emission in atmosphere and prepared catalysts demonstrate the same phthalic anhydride yield but at low reraction temperature. Catalysts, manufactured by mechanochemical treatment (on the base of molybdenum oxide), provide new techniques for producing compounds as exemplified by the direct oxidation of benzene to form phenol which can replace industrial two-step process from cumene or proposed process of benzene oxidation by N2O. Mechanochemistry treatment could produce catalysts which eliminated the need to use highly toxic nitrogen oxides as reducing agents. The article describes activating Cu-Ce-O catalysts which reduce the temperature of the process for removing carbon monoxide from exhaust gases and as a method for purifying hydrogen u sed in fuel cells. Finally, there is a description of mechanochemically treated catalysts, containing metals and supported on stainless steel supports which are used to remove aromatic hydrocarbons from water sewers.

Lurking in the Shadows: The Impact of Emissions Target Setting on Carbon Pricing and Environmental Efficiency

This paper examines the impact of Kyoto Protocol target setting regime on environmental efficiency and carbon shadow pricing. We extract shadow price estimates and efficiency scores from a comprehensive dataset of 125 countries in the first Kyoto commitment period (2008-2012) using a stochastic non-parametric estimation framework. We estimate CO2 marginal abatement costs which: are significantly higher for target setting countries; increase over the sample period, and are an order of magnitude greater than the prevailing emissions pricing mechanisms. Our findings provide insights into the consequences of policies to curb unwanted by-products in a regulated system and shed light on the price efficiency of carbon markets.

Development of a Cofactor Balanced, Multi Enzymatic Cascade Reaction for the Simultaneous Production of L-Alanine and L-Serine from 2-Keto-3-deoxy-gluconate

Enzymatic reaction cascades represent a powerful tool to convert biogenic resources into valuable chemicals for fuel and commodity markets. Sugars and their breakdown products constitute a significant group of possible substrates for such biocatalytic conversion strategies to value-added products. However, one major drawback of sugar cascades is the need for cofactor recycling without using additional enzymes and/or creating unwanted by-products. Here, we describe a novel, multi-enzymatic reaction cascade for the one-pot simultaneous synthesis of L-alanine and L-serine, using the sugar degradation product 2-keto-3-deoxygluconate and ammonium as precursors. To pursue this aim, we used four different, thermostable enzymes, while the necessary cofactor NADH is recycled entirely self-sufficiently. Buffer and pH optimisation in combination with an enzyme titration study yielded an optimised production of 21.3 +/− 1.0 mM L-alanine and 8.9 +/− 0.4 mM L-serine in one pot after 21 h.

Identification of engine oil-derived ash nanoparticles and ash formation process for a gasoline direct-injection engine.

Engine oil-derived ash particles emitted from internal combustion (IC) engines are unwanted by-products, after oil is involved in in-cylinder combustion process. Since they typically come out together with particulate emissions, no detail has been reported about their early-stage particles other than agglomerated particles loaded on aftertreatment catalysts and filters. To better understand ash formation process during the combustion process, differently formulated engine oils were dosed into a fuel system of a gasoline direct injection (GDI) engine that produces low soot mass emissions at normal operating conditions to increase the chances to find stand-alone ash particles separated from soot aggregates in the sub-20-nm size range. In addition to them, ash/soot aggregates in the larger size range were examined using scanning transmission electron microscopy (STEM)-X-ray electron dispersive spectroscopy (XEDS) to present elemental information at different sizes of particles from various oil formulations. The STEM-XEDS results showed that regardless of formulated oil type and particle size, Ca, P and C were always contained, while Zn was occasionally found on relatively large particles, suggesting that these elements get together from an early stage of particle formation. The S, Ca and P K-edge X-ray absorption near edge structure (XANES) analyses were performed for bulk soot containing raw ash. The linear combination approach & cross-checking among XANES results proposed that Ca5(OH)(PO4)2, Ca3(PO4)2 and Zn3(PO4)2 are potentially major chemical compounds in raw ash particles, when combined with the STEM-XEDS results. Despite many reports that CaSO4 is a major ash chemical when ash found in DPF/GFP systems was examined, it was observed to be rarely present in raw ashes using the S K-edge XANES analysis, suggesting ash transformation.

PENGARUH KONSENTRASI ISOPROPANOL TERHADAP KARAKTERISTIK KARBOKSIMETIL SELULOSA DARI BATANG PISANG

In this study consists of 5 stages, namely preparation of raw materials, cellulose isolation, alkalization, carboxymethylization, and purification. The raw material preparation stage is banana stem powder sieved at mesh 60. Furthermore, cellulose isolation of banana stems is carried out with 90% formic acid with a stirring speed of 300 rpm for 180 minutes at 100 0C. Alkalised using 15% NaOH and varying concentrations of 70%, 80%, 90% and 100% isopropanol solvents in a 100 rpm waterbath shaker for 60 minutes at 300C. The next step is carboxymethylation between alkali cellulose and trichloroacetic acid for 180 minutes at 550C in a 100 rpm waterbath shaker. At the purification glacial acetic acid and ethanol are used to remove unwanted by-products. The results characteristics with the highest degree of substitution value of 0.8 in the composition of 100% isopropanol, the highest purity of 99.7%, pH 4.8 and 5% moisture content.