Efficacy of three EPA-registered antimicrobials and steam against two human norovirus surrogates on nylon carpets with two backing types.

Carpet cleaning guidelines currently do not include the use of an antimicrobial, except after a bodily fluid event. To address this gap, we compared the efficacy of three antimicrobials-two hydrogen peroxide-based (H2O2) products (A and B) and one chlorine-based product (C)-and a steam treatment against two norovirus surrogates, specifically feline calicivirus (FCV) and Tulane virus (TuV). These tests were performed on nylon carpets with either water-permeable or waterproof backing types. The effect of repeated antimicrobial use on carpet properties was also evaluated. For a carpet with water-permeable backing, products A, B, and C achieved a 0.8, 3.1, and 0.9 log10 PFU/coupon reduction of FCV and 0.3, 2.5, and 0.4 log10 TCID50/coupon reduction of TuV, respectively, following a 30 min contact time. For carpet with waterproof backing, only product B achieved a 5.0 log10 PFU/coupon reduction of FCV and >3.0 log10 TCID50/coupon reduction of TuV, whereas products A and C achieved a 2.4 and 1.6 log10 PFU/coupon reduction of FCV and a 1.2 and 1.2 log10 TCID50/coupon reduction of TuV, respectively. Steam treatment achieved a ≥ 5.2 log10 PFU/coupon reduction of FCV and a > 3.2 log10 TCID50/coupon reduction of TuV in 15 seconds on the carpet with both backing types. The repeated use of products A and B decreased the tensile strength of the carpet backing, while use of product B resulted in cracks on carpet fibers. Overall, steam treatment for 15 seconds was efficacious on both carpet types, but only product B achieved efficacy after a 30-minute exposure on the carpet with waterproof backing.IMPORTANCECarpets are common in long-term care facilities, despite its potential as a vehicle for transmission of agents associated with healthcare-associated infections, including human norovirus (NoV). Presently, our understanding of carpet disinfection is limited; hence, there are no commercial antimicrobials against norovirus available for use on carpets. Our findings showed that steam treatment, which minimally affected the properties of carpet fibers and backing, was more efficacious against human norovirus surrogates on carpets compared to the three chemical antimicrobials tested. Additionally, the two surrogates were more sensitive to chemical antimicrobials on the carpet with waterproof backing compared to carpets with water-permeable backing. These findings can inform development of antimicrobials for use on carpets contaminated with human norovirus.

The Impact of Repeated Steam Sterilization Cycles on the Efficacy of Chairside Adjustment Kits for Polishing Monolithic Multi-Layered Zirconia Dental Restoration Material.

BACKGROUND Before insertion, chairside adjustment kits are heat sterilized for positioning and polishing dental restorations. This study aimed to evaluate the effects of 2 steam sterilization cycles on the efficacy of polishing highly translucent monolithic zirconia (HTMLZ) dental restoration material. MATERIAL AND METHODS 100 HTMLZ disc-shaped specimens were adjusted (grinding, finishing, polishing) with EVE Diacera kit. Two steam sterilization techniques [standard (Gp S), immediate/flash (Gp (F)] of CAK were further subgrouped based on number of sterilization cycles [cycle 1 (control), cycle 5, 10, 15, and 20 (experimental)] (n=10 each). Each subgroup accordingly was evaluated for average surface roughness (Ra) and root mean square roughness (Rq) using a profilometer. Mean and standard deviation of 5 subgroups were statistically analyzed using one-way ANOVA/post hoc Tukey's test. Scanning electron microscopy complemented Ra, Rq measurements. Statistical differences of P≤0.05 were considered significant. RESULTS HTMLZ specimens in both groups showed increased (Ra/Rq) values after repeated sterilization of EVE Diacera kit, with Gp F showing lesser increase than Gp S (20 cycles). Gp F at 10 cycles and Gp S at 15 cycles showed clinically unacceptable roughness threshold (0.25 µm). Differences between subgroups for Ra and Rq values were significant (P≤0.05) with less differences within groups observed in early cycles (1, 10). Results validate the manufacturer's recommendations of using flash sterilization/10 cycles for EVE Diacera kit. CONCLUSIONS Repeated sterilization reduces efficacy of chairside adjustment kit to produce smooth surfaces on HTMLZ. This study recommends flash sterilization to a maximum of 10 times to get the clinically acceptable results of Ra and Rq.

Safety and performance of the Clearum™ high flux hemodialyzer.

BACKGROUND: Clearum™ is a high flux steam sterilized dialyzer for patients with hemodialysis or hemodiafiltration. This study evaluated the safety and performance of the Clearum high flux steam sterilized hemodialyzer in the removal of small and middle-sized toxins. METHODS: A prospective, interventional, nonrandomized study enrolled twenty end-stage renal disease patients undergoing hemodialysis. The Clearum high flux steam sterilized dialyzer was compared to Fresenius FX dialyzers for baseline comparison. The duration of the trial was 2 weeks for the FX dialyzer and 6 weeks with the Clearum high flux steam sterilized dialyzer. In vitro studies with dextrans of varying sizes were performed to compare the membrane characteristics and sieving coefficient curves for the two dialyzers. RESULTS: The primary objective of a mean urea reduction ratio >65% was met, with no significant difference in mean urea reduction ratio between the Clearum high flux steam sterilized and Fresenius FX-series of dialyzers (p = 0.86). No dialyzer-related adverse events were reported in the study. ß-2-microglobulin reduction with the Clearum high flux steam sterilized dialyzer was statistically higher than the FX-series dialyzer (66.5% vs. 53.6%; p < 0.0001). Predialysis interleukin-6 and C-reactive protein concentrations, blood-rest scores (residual blood after blood restitution), and thrombin-anti-thrombin values were comparable. Albumin remained stable during the 6 weeks of Clearum high flux steam sterilized dialyzer use, with no appreciable differences compared to the Fresenius FX-series. CONCLUSION: The Clearum high flux steam sterilized dialyzer showed good mid-term effectivity for small and middle molecule removal with no reported dialyzer-related adverse events.

Effect of Poly(propylene carbonate) on Properties of Polylactic Acid-Based Composite Films.

To enrich the properties of polylactic acid (PLA)-based composite films and improve the base degradability, in this study, a certain amount of poly(propylene carbonate) (PPC) was added to PLA-based composite films, and PLA/PPC-based composite films were prepared by melt blending and hot-press molding. The effects of the introduction of PPC on the composite films were analyzed through in-depth studies on mechanical properties, water vapor and oxygen transmission rates, thermal analysis, compost degradability, and bacterial inhibition properties of the composite films. When the introduction ratio coefficient of PPC was 30%, the tensile strength of the composite film increased by 19.68%, the water vapor transmission coefficient decreased by 14.43%, and the oxygen transmission coefficient decreased by 18.31% compared to that of the composite film without PPC, the cold crystallization temperature of the composite film increased gradually from 96.9 °C to 104.8 °C, and PPC improved the crystallization ability of composite film. The degradation rate of the composite film with PPC increased significantly compared to the previous one, and the degradation rate increased with the increase in the PPC content. The degradation rate was 49.85% and 46.22% faster on average than that of the composite film without PPC when the degradation was carried out over 40 and 80 days; the composite film had certain inhibition, and the maximum diameter of the inhibition circle was 2.42 cm. This study provides a strategy for the development of PLA-based biodegradable laminates, which can promote the application of PLA-based laminates in food packaging.

Novel techniques for the mass production of nutritionally improved, fungus-treated lignocellulosic biomass for ruminant nutrition.

BACKGROUND: Laboratory-scale experiments have shown that treatment with selective lignin-degrading white-rot fungi improves the nutritional value and ruminal degradability of lignocellulosic biomass (LCB). However, the lack of effective field-applicable pasteurization methods has long been recognized as a major obstacle for scaling up the technique for fungal treatment of large quantities of LCB for animal feeding. In this study, wheat straw (an LCB substrate) was subjected to four field-applicable pasteurization methods - hot-water, formaldehyde fumigation, steam, and hydrated lime - and cultured with Pleurotus ostreatus grain spawn for 10, 20, and 30 days under solid-state fermentation. Samples of untreated, pasteurized but non-inoculated and fungus-treated straws were analyzed for chemical composition, aflatoxin B1 (AFB1 ), and in vitro dry matter digestibility (IVDMD), in vitro total gas (IVGP), methane (CH4 ), and volatile fatty acid (VFA) production. RESULTS: During the 30-day fungal treatment, steam and lime pasteurized straws had the greatest loss of lignin, resulting in marked improvements in crude protein (CP), IVDMD, IVGP, and total VFAs. Irrespective of the pasteurization method, the increase in IVDMD during fungal treatment was linearly (R2 = 0.77-0.92) related to lignin-loss in the substrate during fungal treatment. The CH4 production of the fungus-treated straw was not affected by the pasteurization methods. Aflatoxin B1 was within the safe level (<5 µg kg-1 ) in all pasteurized, fungus treated straws. CONCLUSION: Steam and lime were promising field-applicable pasteurization techniques to produce nutritionally improved fungus-treated wheat straw to feed ruminants. Lime pasteurization was more economical and did not require expensive energy inputs. © 2023 Society of Chemical Industry.

Hibiscus Sabdariffa L. Extract as a Natural Additive in Food Packaging Biodegradable Films to Improve Antioxidant, Antimicrobial, and Physicochemical Properties.

In this study, biodegradable active films were prepared from potato starch and polyvinyl alcohol at different proportions, mixed with acetone extract of Hibiscus sabdariffa L. (HS) and using glycerol as a plasticizer. Functional properties, antimicrobial, and antioxidant capacity were evaluated. Potato starch films with a proportion of polyvinyl alcohol up to 50% and HS extract had significant antioxidant capacity and antibacterial effect against most of the analyzed strains. Adding polyvinyl alcohol (PVOH) and HS extract improved the mechanical performance and reduced water vapor permeability of the materials. The active biobased films with HS extract presented good physicochemical, antimicrobial, and antioxidant properties. These materials are considered as suitable for food packaging, and the active compounds in the roselle extract are a natural antibacterial option for the food area. The materials based entirely on biodegradable products are an excellent alternative when developing and marketing biobased materials, minimizing the environmental impact of food packaging.

Packaging materials and technologies for microwave applications: a review1.

Packaging materials for microwave application should be generally designed based on products properties and processing conditions such as microwavability, susceptibility, processing condition, barrier properties, mechanical properties, storage condition, sustainability, convenience, and so on. Ready-to-eat products are packed in materials that can sustain thermal processing in an industrial oven and warming process in a household oven. In this context, high barrier polymers are versatile microwave packaging materials due to the microwave transparency (unlike metalized film) and high barrier. Additionally, microwave packaging materials used for ready-to-cook are intended to facilitate the microwave heating of the products in a domestic oven. The introduction of a functional feather to microwave packaging tends to improve the microwaving efficiency such as susceptor and shielding in the household oven or self-venting microwave packaging to safely release the internal steam. Furthermore, microwave-assisted thermal processing intends to control microbial contamination, requiring materials with adequate stability during processing and storage. The features of these materials are addressed in this review along with details on the basic requirements and advanced technologies for microwave packaging, microwave processing of prepackaged food, and migration testing. The prospects of microwave packaging materials in the near future are also discussed.

Heterogeneous Nucleation of Supersaturated Water Vapor onto Sub-10 nm Nanoplastic Particles.

Nanoplastic pollution by atmospheric transport processes is a recently discovered environmental problem on a global scale that is attributed to the dispersion of aerosolized nanoplastics. However, knowledge about the basic physicochemical properties of aerosol nanoplastic particles is scarce. Here, we present experiments on the heterogeneous nucleation of supersaturated water vapor onto sub-10 nm polyethylene terephthalate (PET) seeds. We determined onset saturation ratios for the activation of PET seeds in comparison to the well-documented reference system of silver particles, resulting in lower onset saturation ratios of the PET seeds compared to silver seeds. By using different PET bulk materials for the generation of nanoparticles, we report a strong material dependence of the onset saturation ratios, pointing to a strong effect of additives from commodity plastics in heterogeneous nucleation. Moreover, our results show a strong dependence on nucleation temperature that might be of immediate atmospheric relevance. Our work can be considered as an initial step in airborne nanoplastic detection by condensation techniques, and we anticipate our study to serve as a basis for further research that will eventually allow assessing the impact of nanoplastic dispersion on atmospheric processes.

Sewage sludge steam gasification over bimetallic mesoporous Al-MCM48 catalysts for efficient hydrogen generation.

This study explored the potential of steam gasification of sewage sludge over different temperatures (non-catalytic) and bimetallic (Ni-Fe and Ni-Co) mesoporous Al-MCM48 (3-5% Al basis). The higher temperature (800 °C) resulted in higher gas yield (36.74 wt%) and syngas (H2 and CO) selectivity (35.30 vol% and 11.66 vol%). Moreover, catalytic approach displayed that the Al-MCM48 was effective support because the incorporation of nickel increased the efficiency of gasification reactions compared to HZSM-5 (30). It mainly comes from the presence of mesopores and higher surface area (710.05 m2/g) providing more reaction sites and higher stability (less coke formation). Furthermore, the addition of promoters such as Co and Fe allowed the formation of Ni-Fe and Ni-Co alloys, resulting in even higher gas yield and overall H2 and CO selectivity due to the promotion of related reactions such as tar cracking, Boudouard, water gas shift and reforming and so on. Ni-Co alloy catalyst (10% Ni-5% Co/Al-MCM48) resulted in the highest H2 (∼52 vol%) selectivity due to the enhanced Ni dispersion and synergy effect between Ni and Co. Moreover, the application of bi-metal alloy on Al-MCM48 showed no coke formation and significantly reduced CO2 and hydrocarbon selectivity in the product gas. Overall, this study presented a promising solution for sewage sludge disposal in terms of clean H2 generation, reduction in CO2 and higher stability of metal based catalysts at the same time.

The potential of nano graphene oxide and chlorhexidine composite membranes for use as a surface layer in functionally graded membranes for periodontal lesions.

Membranes have been used for treating periodontal defects and play a crucial role in guided bone regeneration applications. Nano graphene oxide have been exploited in tissue engineering due to its biomechanical properties. Its composite formulations with hydroxyapatite and chitosan with controlled degradation could aid in becoming part of a surface layer in a functionally graded membrane. The aim of the study was to synthesize chitosan and composite formulations of nano graphene oxide, hydroxyapatite and chlorhexidine digluconate using solvent casting technique and to characterize the physiochemical, mechanical, water vapor transmission rate (barrier), degradation and antimicrobial potential of the membranes. Altogether four different membranes were prepared (CH, CCG, 3511 and 3322). Results revealed the chemical interactions of hydroxyapatite, chitosan and nanographene oxide due to inter and intra molecular hydrogen bonding. The tensile strength of 3322 (33.72 ± 6.3 MPa) and 3511 (32.06 ± 5.4 MPa) was higher than CH (27.46 ± 9.6 MPa). CCG showed the lowest water vapor transmission rate (0.23 ± 0.01 g/h.m2) but the highest weight loss at day 14 (76.6 %). 3511 showed a higher drug release after 72 h (55.6 %) Significant biofilm growth inhibition was observed for all membranes. 3511 showed complete inhibition against A. actinomycetemcomitans. Detailed characterization of the synthesized membranes revealed that 3511 composite membrane proved to be a promising candidate for use as a surface layer of membranes for guided bone regeneration of periodontal lesions.

Apricot Seed Shells and Walnut Shells as Unconventional Sugars and Lignin Sources.

The present study focuses on using apricot seeds shells and walnut shells as a potential renewable material for biorefinery in Ukraine. The goal of the research work was to determine the relationship between the chemical composition of solid residues from biomass after acid pretreatment with H2SO4, alkaline pretreatment with NaOH, and a steam explosion pretreatment and the recovery of sugars and lignin after further enzymatic hydrolysis with the application of an industrial cellulase Cellic CTec2. Apricot seeds shells and walnut shells consist of lots of cellulose (35.01 and 24.19%, respectively), lignin (44.55% and 44.63%, respectively), hemicelluloses (10.77% and 26.68%, respectively), and extractives (9.97% and 11.41%, respectively), which affect the efficiency of the bioconversion of polysaccharides to sugars. The alkaline pretreatment was found to be more efficient in terms of glucose yield in comparison with that of acid and steam explosion, and the maximum enzymatic conversions of cellulose reached were 99.7% and 94.6% for the solids from the apricot seeds shells and the walnut shells, respectively. The maximum amount of lignin (82%) in the residual solid was obtained during the processing of apricot seed shells submitted to the acid pretreatment. The amount of lignin in the solids interferes with the efficiency of enzymatic hydrolysis. The results pave the way for the efficient and perspective utilization of shells through the use of inexpensive, simple and affordable chemical technologies, obtaining value-added products, and thus, reducing the amount of environmental pollution (compared to the usual disposal practice of direct burning) and energy and material external dependency (by taking advantage of these renewable, low-cost materials).

Volatile Composition, Antimicrobial Activity, and In Vitro Innate Immunomodulatory Activity of Echinacea purpurea (L.) Moench Essential Oils.

Echinacea purpurea (L.) Moench is a medicinal plant commonly used for the treatment of upper respiratory tract infections, the common cold, sore throat, migraine, colic, stomach cramps, and toothaches and the promotion of wound healing. Based on the known pharmacological properties of essential oils (EOs), we hypothesized that E. purpurea EOs may contribute to these medicinal properties. In this work, EOs from the flowers of E. purpurea were steam-distilled and analyzed by gas chromatography-mass spectrometry (GC-MS), GC with flame-ionization detection (GC-FID), and chiral GC-MS. The EOs were also evaluated for in vitro antimicrobial and innate immunomodulatory activity. About 87 compounds were identified in five samples of the steam-distilled E. purpurea EO. The major components of the E. purpurea EO were germacrene D (42.0 ± 4.61%), α-phellandrene (10.09 ± 1.59%), ß-caryophyllene (5.75 ± 1.72%), γ-curcumene (5.03 ± 1.96%), α-pinene (4.44 ± 1.78%), δ-cadinene (3.31 ± 0.61%), and ß-pinene (2.43 ± 0.98%). Eleven chiral compounds were identified in the E. purpurea EO, including α-pinene, sabinene, ß-pinene, α-phellandrene, limonene, ß-phellandrene, α-copaene, ß-elemene, ß-caryophyllene, germacrene D, and δ-cadinene. Analysis of E. purpurea EO antimicrobial activity showed that they inhibited the growth of several bacterial species, although the EO did not seem to be effective for Staphylococcus aureus. The E. purpurea EO and its major components induced intracellular calcium mobilization in human neutrophils. Additionally, pretreatment of human neutrophils with the E. purpurea EO or (+)-δ-cadinene suppressed agonist-induced neutrophil calcium mobilization and chemotaxis. Moreover, pharmacophore mapping studies predicted two potential MAPK targets for (+)-δ-cadinene. Our results are consistent with previous reports on the innate immunomodulatory activities of ß-caryophyllene, α-phellandrene, and germacrene D. Thus, this study identified δ-cadinene as a novel neutrophil agonist and suggests that δ-cadinene may contribute to the reported immunomodulatory activity of E. purpurea.

A Dual Sensing Platform for Human Exhaled Breath Enabled by Fe-MIL-101-NH2 Metal-Organic Frameworks and its Derived Co/Ni/Fe Trimetallic Oxides.

Limited by the insufficient active sites and the interference from breath humidity, designing reliable gas sensing materials with high activity and moisture resistance remains a challenge to analyze human exhaled breath for the translational application of medical diagnostics. Herein, the dual sensing and cooperative diagnosis is achieved by utilizing metal-organic frameworks (MOFs) and its derivative. The Fe-MIL-101-NH2 serves as the quartz crystal microbalance humidity sensing layer, which exhibits high selectivity and rapid response time (16 s/15 s) to water vapor. Then, the Co2+ and Ni2+ cations are further co-doped into Fe-MIL-101-NH2 host to obtain the derived Co/Ni/Fe trimetallic  oxides (CoNiFe-MOS-n). The chemiresistive CoNiFe-MOS-n sensor displays the high sensitivity (560) and good selectivity to acetone, together with a lower original resistance compared with Fe2 O3 and NiFe2 O4 . Moreover, as a proof-of-concept application, synergistic integration of Fe-MIL-101-NH2 and derived CoNiFe-MOS-n is carried out. The Fe-MIL-101-NH2 is applied as moisture sorbent materials, which realize a sensitivity compensation of CoNiFe-MOS-n sensors for the detection of acetone (biomarker gas of diabetes). The findings provide an insight for effective utilization of MOFs and the derived materials to achieve a trace gas detection in exhaled breath analysis.

A high-temperature water vapor equilibration method to determine non-exchangeable hydrogen isotope ratios of sugar, starch and cellulose.

The analysis of the non-exchangeable hydrogen isotope ratio (δ2 Hne ) in carbohydrates is mostly limited to the structural component cellulose, while simple high-throughput methods for δ2 Hne values of non-structural carbohydrates (NSC) such as sugar and starch do not yet exist. Here, we tested if the hot vapor equilibration method originally developed for cellulose is applicable for NSC, verified by comparison with the traditional nitration method. We set up a detailed analytical protocol and applied the method to plant extracts of leaves from species with different photosynthetic pathways (i.e., C3 , C4 and CAM). δ2 Hne of commercial sugars and starch from different classes and sources, ranging from -157.8 to +6.4‰, were reproducibly analysed with precision between 0.2‰ and 7.7‰. Mean δ2 Hne values of sugar are lowest in C3 (-92.0‰), intermediate in C4 (-32.5‰) and highest in CAM plants (6.0‰), with NSC being 2 H-depleted compared to cellulose and sugar being generally more 2 H-enriched than starch. Our results suggest that our method can be used in future studies to disentangle 2 H-fractionation processes, for improving mechanistic δ2 Hne models for leaf and tree-ring cellulose and for further development of δ2 Hne in plant carbohydrates as a potential proxy for climate, hydrology, plant metabolism and physiology.

Mechano-Regulable and Healable Silk-Based Materials for Adaptive Applications.

Mechanically adaptive materials responsive to environmental stimuli through changing mechanical properties are highly attractive in intelligent devices. However, it is hard to regulate the mechanical properties of most mechanically adaptive materials in a facile way. Moreover, it remains a challenge to achieve mechano-regulable materials with mechanical properties ranging from high strength to extreme toughness. Here, inspired by the reversible nanofibril network structure of skeletal muscle to achieve muscle strength regulation, we present a mechano-regulable biopolymeric silk fibroin (SF) composite through regulating dynamic metal-ligand coordination bonds by using water molecules as competitive regulators. Efficient interfacial hydrogen bonds between tannic acid-tungsten disulfide nanohybrids and the SF matrix endow the composite with high mechanical strength and self-healing ability. The resulting composite exhibits 837-fold change in Young's modulus (5.77 ± 0.61 GPa to 6.89 ± 0.64 MPa) after water vapor triggering, high mechanical properties (72.5 ± 6.3 MPa), and excellent self-healing efficiency (nearly 100%). The proof-of-concept ultraconformable iontronic skin and smart actuators are demonstrated, thereby providing a direction for future self-adaptive smart device applications.

The merit of pressure dependent kinetic modelling in steam cracking.

Renewable cracking feedstocks from plastic waste and the need for novel reactor designs related to electrification of steam crackers drives the development of accurate and fundamental kinetic models for this process, despite its large scale implementation for more than half a century. Pressure dependent kinetics have mostly been omitted in fundamental steam cracking models, while they are crucial in combustion models. Therefore, we have assessed the importance of pressure dependent kinetics for steam cracking via in-depth modelling and experimental studies. In particular we have studied the influence of considering fall-off on the product yields for ethane and propane steam cracking. A high-pressure limit fundamental kinetic model is generated, based on quantum chemical data and group additive values, and supplemented with literature values for pressure dependent kinetic parameters for ß-scission reactions and homolytic bond scissions of C2 and C3 species. Model simulations with high-pressure limit rate coefficients and pressure dependent kinetics are compared to new experimental measurements. Steam cracking experiments for pure ethane and propane feeds are performed on a tubular bench-scale reactor at 0.17 MPa and temperatures ranging from 1058 to 1178 K. All important product species are identified using a comprehensive GC × GC-FID/q-MS. For homolytic bond scissions, the inclusion of pressure dependent kinetics has a significant effect on the conversion profile for ethane steam cracking. On the other hand, pressure dependence of C2 ß-scissions significantly influences conversion and product species profiles for both ethane and propane steam cracking. The C3 ß-scissions pressure dependence has a negligible effect in ethane steam cracking, while for propane steam cracking the effect is non-negligible on the product species profiles.

Reversibly Phase-Transformative Zeolitic Imidazolate Framework-108 and the Membrane Separation Utility.

Reversible phase transformations (RPTs) of metal-organic frameworks not only create material diversity but also promise a self-restoration of crystals in a controllable manner. However, there are only limited examples because seeking for a convenient and effective trigger for RPTs, especially for RPTs with respect to spatiotemporal harmony in cleavage and reconstruction of metal-linker chemical bonds, is challenging. In this work, we found that zeolitic imidazolate framework (ZIF)-108 with Zn-N coordination bonds showing moderate strength was an ideal platform. We reported three crystal phases of ZIF-108, namely, sodalite (SOD), diamondoid (DIA), and large pore_sodalite (lp_SOD) topologies, and identified RPTs between phases: (1) when exposed to water or water vapor, the SOD structure could transform to a compact DIA version as a result of the decomposition of four-membered rings and synchronous reorganization of six-membered rings. Then, the DIA structure could also return back to SOD when soaked in dimethylformamide (DMF) or DMF vapor. (2) High-temperature treatment of SOD gives rise to lp_SOD, which then reverts to SOD by DMF. (3) lp_SOD could also be compressed into the DIA phase by water or water vapor and can then be restored via a two-step treatment, namely, soaking in DMF (DIA → SOD) right before a high-temperature therapy (SOD → lp_SOD). From the perspective of the separation utility, we found that the lp_SOD version of ZIF-108, relative to SOD-structured ZIF-108, can produce mixed matrix membranes having an interesting interfacial structure with the polymer chains, though both share the same chemical composition. We verified that the large pore of lp_SOD can allow being penetrated by polymer chains, which contributed to not only reinforcing the bi-phase interface but also sharpening the molecule sieve properties of fillers toward CO2 and CH4.

A systematic construction of water-electricity cogeneration and thermal membrane coupling desalination technology using the waste heat in steel industry.

The widespread use of fossil energy emits a large amount of carbon dioxide, leading to the greenhouse effect and global warming. The essence of reducing carbon emissions is to achieve higher-quality sustainable development. The recycling of waste heat in the iron and steel industry is of great significance to reducing carbon emissions. Aiming at the problem of insufficient utilization of gas in iron and steel industry and the development of seawater desalination industry, a water-electricity cogeneration and thermal membrane coupling technology is established. Low-temperature multi-effect distillation seawater desalination device is directly connected with steam turbine generator, which uses gas to generate electricity. After generating electricity, negative pressure exhaust at the end of steam turbine is used for seawater desalination. The thermal efficiency of the system is increased to over 80%, the waste heat is effectively utilized, and the carbon emission in the thermal desalination process is reduced. At the same time, the high-efficiency removal and resource utilization of salt in concentrated seawater are realized. The recovery ratio of freshwater is over 55%, the salt content of freshwater is below 500 mg/L, and the salt content of seawater concentrated by membrane method can reach 79,450 mg/L. A new comprehensive utilization and recycling system of seawater has been constructed to realize efficient recycling of energy resources and promote the development process of carbon emission reduction.

Simultaneous quantification of volatile fatty acids and nonvolatile organic acids in Hevea brasiliensis latex.

The current method used in latex industries to determine the volatile fatty acids contents of Hevea brasiliensis latex is steam distillation. However, the accuracy of the method has been debated for some time. We assessed the accuracy of the method and developed a new, more reliable high-performance liquid chromatographic method of determining acids in latex. The volatile fatty acids (formic, acetic, propionic, butyric, and valeric acids) and nonvolatile organic acids (oxalic, malic, lactic, citric, and succinic acids) in latex are directly determined simultaneously for the first time with high sensitivity and without losses during sample preparation. To avoid errors from derivatization, an acid-resistant Prevail HPLC column and a gradient mobile phase of 25 mM potassium dihydrogen phosphate (pH 2.5) and acetonitrile were employed. Under optimum conditions, the calibrations of both types of acids demonstrated satisfactory correlation coefficients of  ≥0.990, with limits of detection ranging from 0.02 to 395 mM. The developed method demonstrated the profiles of acids in field and concentrated latex of the same batch. Moreover, the evolution of the profiles of all studied acids in both types of latex during a 3-month period was also revealed.

Efficacy of cleaning and sanitation methods against Listeria innocua on apple packing equipment surfaces.

Previous foodborne listeriosis outbreaks and recalls of fresh produce have been linked to cross-contamination with food contact surfaces (FCS) of packing equipment. Thus, effective cleaning and sanitation practices should be implemented in the short-term to contribute to the overall food safety objective for FCS which have a suboptimal hygienic design. This research aimed to evaluate the efficacy of seven cleaning and sanitation treatment combinations against Listeria innocua populations on FCS common to produce packinghouses that have been found to have a higher prevalence of Listeria spp. harborage. Polishing brushes made of two different materials (100% nylon and nylon/horsehair mix), 100% polyethylene wash brushes, stainless steel rollers and polytetrafluorethylene (Teflon®) wrapped rollers, and interlocking conveyor belts were evaluated (n = 6 per treatment). These FCS were inoculated with L. innocua (9 log CFU/mL) and fouled with food-grade wax, with the exception of brush rollers that are encountered before waxing. Treatments included the use chlorine (200 ppm), peroxyacetic acid (PAA) (500 ppm) for 15 min, alone or in combination with an alkaline detergent (1.6%) or a degreaser, and the use of steam at 95 °C for 15 s. L. innocua was enumerated and the log reduction was calculated and compared to untreated controls. Horsehair mix polishing brushes were the surface with the lowest log reduction regardless of treatment applied (p < 0.05). Compared to 100% nylon polishing brushes, where a >3 log reduction was reached, horsehair mix brushes only reached this level of reduction when degreaser + PAA was applied. For both types of rollers and interlocking conveyor belt, an effective wax removal using a degreaser or detergent followed by sanitizer application caused the greatest L. innocua reduction (>5 log reduction). The application of steam did not show a significant log reduction on any surface (p > 0.05). This study highlights that cleaning and sanitation strategies must focus on effective wax removal if applied postharvest. In addition, 100% nylon polishing brushes could potentially offer a better hygienic design in produce packinghouses compared to the horsehair mix.