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Even though catalyst loading is one of the first crucial steps in organic and inorganic catalytic reactions, it has not been frequently discussed or improved to date. In particular, when a solid catalyst is added to an oxygen- and moisture-sensitive reaction mixture, a carefully tuned process to ensure an inert atmosphere (under nitrogen or argon) is required. Although gloveboxes are nowadays considered to be a universal solution, it is still associated with unsolved problems, such as high cost, high space consumption, difficult temperature control, and handling difficulties on account of the gloves. Herein, we report a recently developed simple apparatus that enables the addition of a solid without opening the reaction vessel. This solid-addition funnel drastically improved the yield (from trace to 64%) and the reproducibility of our original glycosylation reaction.

Based on the theory of porous media, the multifield coupling problem of heat–moisture–salt in unsaturated layered soil under the steady condition is studied considering that the pore of unsaturated soil is filled with liquid water, dissolved salt, water vapour and dry gas. Based on the conservation of mass and energy equations, the paper discusses the mass conservation equations and energy conservation equations for water, gas and salt in unsaturated soils. Considering the one-dimensional steady-state problem, the state equations are obtained by selecting temperature, pore air pressure, pore water pressure and salt solution concentration and their derivatives as the state variables. Under the condition of the boundary values of adjacent soil layers in a given unsaturated soil, the non-linear variable coefficient differential equations are solved by using the shooting method and the validity of the model is verified by comparing with existing steady-state experimental results. Based on numerical examples, the differences in temperature field, pressure field and salinity field between unsaturated layered soil and homogeneous soil are analysed.

Pollution resulting from terrestrial and aquatic trace elements has become a severe problem across the world. Organic carbon (OC) content has a high affinity for metallic contaminants and it acts as a significant sink for trace elements. The decomposition of OC content directly influences the bioavailability of trace elements. The decomposition of OC content and OC distribution vary spatially, these processes affect the release of trace elements and need further research. In the current study, sediment samples from the surface sediment along Beiyun River (Section 1 to Section 4 from upper to lower reaches), which is situated in the rapidly urbanized Beijing metropolis, were measured for OC, moisture, hardness, and trace elements. The OC contents were found to have a substantial difference among all four river sections along the urbanized river gradient. Whereas the higher OC contents were found in sections 2 (Urbanized uplands) and 3 (farmland) compared to those in sections 1 (forest) and 4 (farmland and part of constructed areas). On the other hand, the highest value of the correlation coefficient was found among the different values of trace elements and OC content in the riverine zone of the Beiyun River basin. OC contents play a vital role in the transformation and origin of trace elements in the surface sediment of the Beiyun River basin. The One-way Analysis of Variance (ANOVA) was applied to compare the means of OC and trace elements at different sections indicating no significant difference. However, source identification of trace elements indicated that a geogenic source was responsible for higher contents of arsenic (As) and manganese (Mn) (69.95%). Simultaneously, the natural OC, agricultural activities, and industrial waste contributed about (21.10%) towards the cadmium (Cd) and zinc (Zn), and about 10% for chromium (Cr) and copper (Cu). The current study concludes that the absolute principle component analysis-multiple linear regression (APCA-MLR) method can be successfully be used to investigate the trace elements (Zn, nickel [Ni], lead [Pb], Mn, Cd, Cu, and As) interactions through OC content resulting in determination of the various sources of contamination to cause negative environmental impacts on the ecosystem and human health. So, the current study provides a baseline for a quantitative evaluation of trace elements under different sediment of OC contents.

A growing body of evidence suggests that the increase of permeability results in reduced strength and bearing capacity of subgrade. A new microbiological stabilizing method, known as microbial induced calcite precipitation (MICP), was induced into stabilization of the subgrade for fully permeable pavement in this study. This study explored the mechanical and hydraulic properties of unsaturated and saturated fine sand soil stabilized by MICP technology. Instead of bacteria, urease was directly induced into fine sand with pre-mixing method. The results indicated that saturated specimens obtained better moisture stability. Compared with cement stabilized soil, the compressive strength and resilient modulus of unsaturated urease stabilized soil were lower under the same CaCO3 or cement content. What stands out in this study is that the saturated urease stabilized soil was not sensitive to water and had relatively higher strength. In addition, the hydraulic conductivity of urease stabilized soil was significantly higher than that of cement stabilized soil. This study developed a potential subgrade improvement technology for possible application in fully permeable pavement. Urease stabilizing method could be used to help increase the strength and maintain a high hydraulic conductivity.

This work presents the effects of several factors on the mechanical strength of calcium phosphate cement (CPC) based on alpha tricalcium phosphate and correlates the results with the microstructure and percentage of conversion to hydroxyapatite. Conversion rate increased by raising the setting temperature in the studied range (4–90 °C), but the strength exhibited an increasing-decreasing trend due to changes in the morphology of hydrated crystals. Plate-like crystals were formed in the range of 22–60 °C, mechanically reinforcing the material, whereas the formation and refinement of needle-like crystals at higher setting temperature decreased the strength. Moreover, cements with dissimilar particle sizes had different optimal hydrolysis temperatures that resulted in the maximum strength. The finest powder led to higher strength at lower setting temperature due to the formation of a more compact crystal network and higher conversion. Therefore, optimization of powder particle size may allow to achieve the highest possible strength at room temperature, being beneficial for the production of the strong pre-set CPC-based implants without the use of energy. Furthermore, the particle size can be also engineered to produce formulations that develop the highest strength at physiological temperature, with application as injectable bone grafts. The incorporation and crosslinking of gelatine further increased the mechanical strength of pre-set cements by bridging the hydroxyapatite crystals, the setting temperature showing a similar effect to that of gelatine-free cements. In contrast, moisture decreased the strength and reduced the brittleness by the solvating intramolecular association between hydroxyapatite crystals and between gelatine molecules. Moreover, large cement bodies were slightly weaker than small ones, but the size effect was not statistically significant.

The content and composition of wheat storage proteins are the major determinants of dough rheological properties and breadmaking quality and are influenced by cultivation conditions. This study aimed to investigate the effects of water deficit and high N-fertilizer application on wheat storage protein synthesis, gluten secondary structure, and breadmaking quality. Reverse-phase ultrahigh-performance liquid chromatography analysis showed that storage protein and gluten macropolymer accumulation was promoted under both independent applications and a combination of water-deficit and high N-fertilizer treatments. Fourier-transform infrared spectroscopy showed that water deficit and high N-fertilizer treatments generally improved protein secondary structure formation and lipid accumulation, and reduced flour moisture. In particular, high N-fertilizer application increased β-sheet content by 10.4% and the combination of water-deficit and high N-fertilizer treatments increased random coil content by 7.6%. These changes in gluten content and secondary structure led to improved dough rheological properties and breadmaking quality, including superior loaf internal structure, volume, and score. Our results demonstrate that moderately high N-fertilizer application under drought conditions can improve gluten accumulation, gluten secondary structure formation, and baking quality.

Hypothesis One prevailing method to construct excellent temperature tolerance/long-lasting moisture hydrogels is to couple the original hydrogel networks with freezing-tolerant/moisture retaining agents, including ionic liquids, inorganic salts, zwitterionic osmolytes, and polyhydric alcohols. Among them, organohydrogels have shed new light on the development of ionic skins with long-term usability and stable sensing performance at subzero temperatures due to their long-lasting water retention and anti-freezing capability. Experiments We report a dual network organohydrogel by doping conductive ZnSO4 into the double network hydrogel of polyvinyl alcohol-polyacrylamide (PVA-PAM) with subsequent immersing in a mixed solvent of ethylene glycol (EG) and H2O. The anti-freezing and moisture retaining abilities of the PVA/PAM/Zn/EG (PPZE) organohydrogel were studied and the sensing performances of the PPZE organohydrogel-based ionic skin were investigated. Findings The organohydrogel exhibits a high conductivity (0.44 S m−1), excellent fatigue resistance and exceptional moisture retaining ability with more than 99.3% of the initial weight retention after 31 days storage at ambient temperature. Importantly, the PPZE organohydrogel-based ionic skin shows an ultra-low temperature anti-freezing ability and remains flexibility and sensing capability with a high sensitivity (signal response time ∼ 0.23 s) even at -50 °C. The PPZE organohydrogel demonstrates a tremendous potential in artificial skin and health monitoring.

The liquid phase was proved to be a significant influencing factor among the three phases in solid-state fermentation (SSF), which determined water control was crucial. However, obvious water loss was caused by microbial utilization and moisture evaporation. Super absorbent polymer (SAP) was utilized to supply water in SSF owing to its high water-holding capacity. Adding 0.15% SAP could significantly increase the biomass of Ganoderma lucidum by 33.59% and promote filter paper activity (FPA), endocellulase activity and laccase activity by 27.11%, 29.14% and 47.39%, respectively. Water states of fermentation substrates were detected by the low-field nuclear magnetic resonance (LF-NMR). Results revealed that water present and lost was dominated by the capillary water. At the end of fermentation, the capillary water content ( C cw ) in water-supply SSF was 20.48% and 17.20% higher than that in static SSF and cold-model SSF. The relaxation time of the capillary water was reduced by 56.53% in water-supply SSF and by 53.40% in static SSF, but it just reduced by 6.82% in cold-model SSF. In addition, the C cw in SSF had a high correlation with the biomass and lignocellulose-degrading enzyme activities of G. lucidum. These results clearly demonstrated that capillary water played a very important role in improved production of G. lucidum.

Moisture adsorption isotherm potentials and energy models of Gongronema latifolium leaf grits were investigated. Fresh leaves were dried in sun; passive solar dryer and hot air oven, while proximate composition of the dried and fresh leaves were determined using standard laboratory procedure. Equilibrium moisture content (EMC) of the leaf grits was measured using gravimetric static method. Selected mathematical and statistical models were applied on the experimental data to evaluate data fitting. Energy calculations were done based on the mathematical models. The EMCs of the leaf grits directly increased with water activity (aW) at specific temperatures. Adsorption data was better represented by GAB model than others while differential enthalpy decreased as the EMC of the oven sample increased. Differential entropy of all the samples decreased as the EMC increased. The safest monolayer moisture content varied between 7.1036 and 8.0164 gH2O/100 g solid, below 40°C, within relative humidity of 10%–50%. Sun and oven leaf grits adsorbed more moisture than solar sample. Proximate contents of the dried leaves showed higher values for protein and ash. Overall results indicated that the leaf grits when properly packaged could be used as spice or tea powder to manage household nutrient security in addition to the use as therapeutic foods.

Coal bed methane (CBM) extraction keeps on going through innovative work. Concerns incorporate evaluating the asset, distinguishing good geologic creation zones, setting up effective recuperation plans, exhibiting progressed penetrating advancements and supporting catch and utilization of less available gas streams. Coal of Raniganj field has a unique characteristic incorporating the best non-coking coalfield in India. Proximate analysis indicate that the ash content is less than 20% and the content of volatile matter, fixed carbon and moisture are in the desired range. X-ray diffraction (XRD) examination demonstrates the presence of 48.1% C4H6O6 that is of monoclinic crystal framework and continuous expansion in diffraction band from 198 to 98 at 2θ = 17.62 and 20.0001 Angstrom representing a better coal seam and presence of aliphatic compounds. FT-IR study reveals the presence of aliphatic hydrocarbons associated with CH2 stretching at 2100.05 cm−1, aromatic C=C (1637.92 cm−1) band associated with –OH(3439.95 cm−1) stretching vibrations.

Replacing metals with fiber reinforced polymer (FRP) composites in the marine structure can successfully solve the deterioration question of steel or other materials owing to moisture. On exposure to saltwater environments, the ageing of fibre-reinforced polymer composites has been a crucial concern. For better elaboration, the paper summarizes the mechanical and dynamic properties of FRP when exposed to seawater and other ageing media like distilled water and temperature ageing. It is revealed that the rate of degradation of properties of FRP increased with duration, temperature, and the alkalinity of immersion solution. Apart from reducing the service life of the polymer composite, exposure to moisture results in alteration of physical, chemical, or mechanical properties of polymers. Currently, the investigation of dynamic properties of FRP after prolonged exposure to moisture is relatively restricted. Hence, this study detects probable research demands by briefing current progress in moisture absorption study and the resultant effects on fibre reinforced composite materials' mechanical and dynamic properties.

In mining, particularly for phosphates, extraction is a crucial step. This phase presents several problems that must be treated to optimize ore flow. Among those constraints we find clogging of phosphate ore on different metal supports. It is therefore necessary to understand the factors behind this phenomenon to control it. We focused, in this paper, on the mechanical and thermal characterization of natural phosphate under different conditions of pressure, temperature and humidity. First, we evaluated the compressive strength of raw phosphate, to determine the threshold pressure, which lead to a compact solid phase. We also measured its different limits of friability. Secondly, we studied the structural properties of phosphate ore as a function of temperature and water content. This study was carried out using heating and water adsorption protocols. The results show that phosphate ore compacts easily when subjected to high pressures. In addition, it becomes easily friable when the mass handled is high. Furthermore, the source of phosphate, as well as external conditions, play an important role in its ability to lose moisture, which is the main reason for agglutination.

Global efforts to feed the burgeoning population have focused on increasing food production and access. In the meantime, FAO estimates about 1/3 food loss in the developing countries. To minimize these losses, grain storage techniques were investigated in an earthquake hit village in Kavre district of Nepal. Pesticide free moisture proof/airtight food storage bags were provided to 1,055 households using financial support from UNICEF-Nepal. Thirty-three households were identified who could store food grains for 6-month for this study. Maize and rice grains were stored in porous and in moisture-proof hermetic bags. Food grain samples were collected at the beginning and at 6-month and were analyzed for physical quality parameters, nutrients and mycotoxins. About 92% insect damage occurred in maize stored in porous bags which was prevented in triple layer hermetic Purdue Improved Cowpea Storage (PICS) bags. Insect damage in paddy remained low within 10% in both treatments. Major maize nutrient loss occurred through insect damage. The traditional practice was to use insect and mold infested maize as feed. Mycotoxins results showed that toxigenic molds develop in open storage of improperly dried grains especially maize. Fusarium-related mycotoxins associated with stunting were detected in maize samples using LC-MS/MS equipment. Mature grains should be dried sooner to processing moisture contents and packaged into moisture-proof hermetic bags (Dry Chain) to minimize postharvest loss. A clear policy implication is that use of improved low-cost Dry Chain technology should be promoted to enable quality food systems.

Drying fruits and vegetables is a long-established preservation method, and for tomatoes, in most cases sun-drying is preferred. Semi-drying is relatively a new application aimed to preserve better the original tomato properties. We have assessed the effects of different drying methods on the phytochemical variation in tomato products using untargeted metabolomics and targeted analyses of key compounds. An LC-MS approach enabled the relative quantification of 890 mostly semi-polar secondary metabolites and GC–MS analysis in the relative quantification of 270 polar, mostly primary metabolites. Metabolite profiles of sun-dried and oven-dried samples were clearly distinct and temperature-dependent. Both treatments caused drastic changes in lycopene and vitamins with losses up to > 99% compared to freeze-dried controls. Semi-drying had less impact on these compounds. In vitro bioaccessibility analyses of total phenolic compounds and antioxidants in a gastrointestinal digestion protocol revealed the highest recovery rates in semi-dried fruits. Semi-drying is a better way of preserving tomato phytochemicals, based on both composition and bioaccessibility results. © 2022 Elsevier Ltd

Due to several important limitations for packaging applications of starch film such as strength and hydrophilicity, rice starch (Oryza sativa) film was crosslinked with citric acid and modified by different contents of calcium oxide. FTIR spectra showed the evidence of crosslinking by citric acid and the presence of calcium oxide in the modified rice starch films. After the crosslinking, the decrease of degree of crystallinity and swelling including the increase of film smoothness and strain at maximum load were observed. The application of both citric acid and calcium oxide caused greater decrease of swelling, moisture uptake as well as higher stiffness and antibacterial activity than those of the use of only the citric acid. The highest stiffness and antibacterial activity were found for the crosslinked film added by 5 wt% calcium oxide. Moreover, the effect of calcium oxide contents on morphological, thermal and biodegradable properties of the crosslinked films was also investigated.

Nanotechnology has proven as progressive technology that enables to contribute, develop several effective and sustainable changes in food products. Incorporating nanomaterials like TiO2, SiO2, Halloysite nano clay, Copper sulfide, Bentonite nano clay, in carrageenan to develop innovative packaging materials with augmented mechanical and antimicrobial properties along with moisture and gas barrier properties that can produce safe and healthy foods. Intervention of carrageenan-based bio-nanocomposites as food packaging constituents has shown promising results in increasing the shelf stability and food quality by arresting the microbial growth. Nanomaterials can be incorporated within the carrageenan for developing active packaging systems for continuous protection of food products under different storage environments from farm to the fork to ensure quality and safety of foods. Carrageenan based bio nanocomposite packaging materials can be helpful to reduce the environmental concerns due to their high biodegradability index. This review gives insight about the current trends in the applications of carrageenan-based bio nanocomposites for different food packaging applications.

With the mission of negative emission, moisture swing sorbents are developing fast in recent years, thanks to their low energy consumption and simple operating system. The sorbent was proposed to capture CO2 directly from ambient air, while its low energy-cost nature underpins carbon capture from a variety of other gas streams with larger CO2 concentrations. The present study exploits the moisture swing process for capturing industrial process CO2, and the CO2 removal from natural gas is used for demonstration. Compared to capturing CO2 from the air, the adsorption capacity is promoted significantly as the CO2 concentration in the gas mixture is much higher (1–20%). A stable cyclic capacity with ∼1.0 mmol/g is obtained, which is comparable to that of aqueous/solid amine sorbents. Moreover, a moisture swing process flow is developed for CO2 removal from natural gas, and an energy consumption analysis of the moisture swing process is conducted with comparison to the traditional amine scrubbing technique. We find that the energy consumption of the moisture swing decarbonization process (∼187.38 kJ/Sm3) is less than half that of the methyl diethanolamine solution method (954–1304 kJ/Sm3), which strongly supports the moisture swing process as a promising method for capturing industrial process CO2.

In the present work, the GHARS and the MECH DEGLA downgraded date varieties were used in a fermentation medium in order to produce citric acid by the Aspergillus niger. The biochemical characteristics of the dates were investigated, along with the chemical and physical characteristics of the solutions of both samples. The analyzed parameters included the moisture and sugar content, the ash residual, the pH values, and the electrical conductivity. The effect of the following fermentation parameters was studied: initial pH, temperature, incubation period, and methanol. For the GHARS and MECH DEGLA date varieties respectively, the ash residual measured at 1.90% and 2.47%. For each date variety, the moisture and total sugars were measured at 11.59% and 85%, for the GHARS, and 12.82% and 80.47% for the MECH DEGLA. Citric acid production using either of the two varieties of dates showed a high yield in a short time. The obtained results showed that the highest production of citric acid by both medium of dates was achieved at the initial pH value of 3.0, temperature 30 °C, and an incubation period of 8 days. Also, the maximum amount of citric acid was produced when both mediums contained 4% of methanol. Both varieties of dates showed a good yield for the citric acid and can be used as a culture medium since they are economic and ensure good growth for the Aspergillus niger.

Objective: The objective of this study was to explore the effects of maize straw treated with calcium oxide (CaO) and various moisture, on the composition and molecular structure of the fiber, and gas production by fermentation in an in vitro rumen environment.Methods: The experiment used 4×3 Factorial treatment. Maize straws were treated with 4 concentrations of CaO (0%, 3%, 5%, and 7% of dry straw weight) and 3 moisture contents (40%, 50%, and 60%). Scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray fluorescence spectroscopy were employed to measure the surface texture, secondary molecular structure of carbohydrate, and calcium (Ca) content of the maize straw, respectively. The correlation of secondary molecular structures and fiber components of maize straw were analyzed by CORR procedure of SAS 9.2. In vitro rumen fermentation was performed for 6, 12, 24, 48, and 72 h to measure gas production.Results: Overall, the moisture factor had no obvious effect on the experimental results. Neutral detergent fiber (NDF), acid detergent fiber, acid detergent lignin, hemicellulose and cellulose contents decreased (p

High-performance perovskite solar cells (PSCs) are readily degradable by moisture, leading to high demand for a water-repelling efficient hole transport layer (HTL). In this study, we proposed an a...

More and more people concern about supplementing dietary food with wheat bran to increase fibre content, but there has been little study of the sorption isotherms and isosteric heats of wheat bran fibre products, which are important to the quality and storage durability of such commodities. This study collected equilibrium moisture content (EMC) and equilibrium relative humidity (ERH) data on six Chinese wheat bran products via the static gravimetric method and analysed their sorption isosteric heats. Results showed that all six wheat bran products had sigmoidal isotherms. The data were best fitted by polynomial, modified GAB, modified Oswin, and modified Halsey models. The relative safe moisture contents of the six wheat bran products were 12.20%–13.86% wet basis (w.b.). The heat of vaporization of wheat bran products approached the latent heat of pure water at around a moisture content (MC) of 22.5% and approximately 2450 kJ/kg. A process of extrusion and ultrafine grinding reduced the solid surface area and sorption isosteric heats of the monolayer, multilayer and condensed water regions in the wheat bran products. In the temperature range of 10–37 °C, the EMC of sorption in monolayer, multilayer and condensed water regions decreased with increasing temperature. The milled rice to which 1%–3% 200-mesh wheat bran product was added maintained its texture when made into cooked rice and its thermomechanical properties when made into rice dough. After processing by extrusion and ultrafine grinding, wheat bran products have a lower solid surface area and lower monolayer water content (Mm) and sorption isosteric heat values. Some 3% 200-mesh wheat bran product can be added to cooked rice for increasing its fibre content and making it more nutritious.

Anticipating the harvest period of soybean crops can impact on the post-harvest processes. This study aimed to evaluate early soybean harvest associated drying and storage conditions on the physicochemical soybean quality using of mathematical modeling and multivariate analysis. The soybeans were harvested with a moisture content of 18 and 23% (d.b.) and subjected to drying in a continuous dryer at 80, 100, and 120 °C. The drying kinetics and volumetric shrinkage modeling were evaluated. Posteriorly, the soybean was stored at different packages and temperatures for 8 months to evaluate the physicochemical properties. After standardizing the variables, the data were submitted to cluster analysis. For this, we use Euclidean distance and Ward's hierarchical method. Then defining the groups, we constructed a graph containing the dispersion of the values of the variables and their respective Pearson correlations for each group. The mathematical models proved suitable to describe the drying kinetics. Besides, the effective diffusivity obtained was 4.9 × 10–10 m2 s−1 promoting a volumetric shrinkage of the grains and influencing the reduction of physicochemical quality. It was observed that soybean harvested at 23% moisture, dried at 80 °C, and stored at a temperature below 23 °C maintained its oil content (25.89%), crude protein (35.69%), and lipid acidity (5.54 mL). In addition, it is to note that these correlations' magnitude was substantially more remarkable for the treatments allocated to the G2 group. Furthermore, the electrical conductivity was negatively correlated with all the physicochemical variables evaluated. Besides this, the correlation between crude protein and oil yield was positive and of high magnitude, regardless of the group formed. In conclusion, the early harvest of soybeans reduced losses in the field and increased the grain flow on the storage units. The low-temperature drying and the use of packaging technology close to environmental temperatures conserved the grain quality.