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A series of Al2O3 sols were prepared by HNO3 catalysis of aluminum isopropoxide (AIP), using different molar ratios of HNO3/AIP (nH). The changes in sol densities, viscosities, refractive i...

In the present work, zirconium nitrate pentahydrate (Zr(NO3)4·5H2O) was used as ZrO2 precursors. The ZrO2-SiO2 sols with the Zr/TEOS molar ratios (nZr) ranging from 0 to 2.0 were synthesized by two...

Background: Nitrogen (N), phosphorus (P), and potassium (K) are important essential nutrients for plant growth and development, but how they regulate plant energy status remains unclear. Results: In this study, we grew Nipponbare rice (Oryza sativa) seedlings in a growth chamber for 20 d at 30/24 ℃ (day/night) under natural sunlight conditions with different nutrient regimes. N appeared to play the most important role in plant growth and development, followed by P and K. The highest nonstructural carbohydrate (NSC) content, dry weight, net photosynthetic rate (PN), ATP content, and NADH dehydrogenase, cytochrome oxidase, and ATPase activities were found in the plants that received sufficient N, P, and K. The lowest values of these parameters were measured in the N-deficient plants. Higher dry matter accumulation was observed in the −K treatment than in the −P treatment, but there was no difference in the ratio of respiration rate to photosynthetic rate between these two treatments, suggesting that differences in energy production efficiency may have accounted for this result. This hypothesis was confirmed by higher ATP contents and activities of NADH dehydrogenase, cytochrome oxidase, and ATPase in the K-deficient plants than in the P-deficient plants. Conclusion: We inferred that N, P, and K controlled rice plant growth and development by regulating the efficiency of energy production.

The dissemination of antibiotic resistance genes (ARGs) in food waste (FW) disposal can pose severe threats to public health. Lipid is a primary composition in FW, while whether lipid stress can affect ARGs dynamics during anaerobic digestion (AD) process of FW is uncertain. This study focused on the impacts of lipid stress on methane production, fate of ARGs and its microbial mechanisms during AD of FW. Results showed that high lipid content increased methane yield but prolonged hydrolysis and lag time of methane production compared to AD of FW without oil. Moreover, variations of ARGs were more susceptible to lipid stress. Lipid stress could facilitate the reduction of total ARGs abundances compared to the group without oil, particularly restraining the proliferation of sul1, aadA1 and mefA in AD systems (P

Low methanogenic efficiency caused by excess acidification is a challenge during anaerobic digestion. This study indicated that both granular activated carbon (GAC) and powdered activated carbon (PAC) promoted the start-up of methanogenesis and methane output in anaerobic co-digestion of food waste and fruit-vegetable waste. Moreover, PAC performed better than GAC. Specifically, the highest cumulative methane yield and shortest lag phase were observed in 5 g/L PAC and 10 g/L PAC group, 22.0% higher and 62.5% shorter than that without activated carbon supplementation, respectively. PAC facilitated the methane productivity by effectively accelerating volatile fatty acids (VFAs) consumption and thereby alleviating acidification. Syntrophic VFAs oxidizing bacteria (Gelria and Syntrophomonas) and direct interspecies electron transfer related microorganisms (Geobacter and Methanosarcina) were remarkably enriched by PAC. Furthermore, metagenomic analysis showed that both PAC and GAC might facilitate the electron transfer between microbes by acting as the electrical bridge and enhance both hydrogenotrophic and aceticlastic pathways.

Background Glutathione (GSH) is important for plants to resist abiotic stress, and a large amount of energy is required in the process. However, it is not clear how the energy status affects the accumulation of GSH in plants under cold stress. Results Two rice pure lines, Zhongzao39 (ZZ39) and its recombinant inbred line 82 (RIL82) were subjected to cold stress for 48 h. Under cold stress, RIL82 suffered more damages than ZZ39 plants, in which higher increases in APX activity and GSH content were showed in the latter than the former compared with their respective controls. This indicated that GSH was mainly responsible for the different cold tolerance between these two rice plants. Interestingly, under cold stress, greater increases in contents of carbohydrate, NAD(H), NADP(H) and ATP as well as the expression levels of GSH1 and GSH2 were showed in RIL82 than ZZ39 plants. In contrast, ATPase content in RIL82 plants was adversely inhibited by cold stress while it increased significantly in ZZ39 plants. This indicated that cold stress reduced the accumulation of GSH in RIL82 plants mainly due to the inhibition on ATP hydrolysis rather than energy deficit. Conclusion We inferred that the energy status determined by ATP hydrolysis involved in regulating the cold tolerance of plants by controlling GSH synthesis.

Coking wastewater (CWW) is one of the most challenging industrial wastewaters to treat, due to its complex chemical composition, high organic load, and potential toxicity to human and environmental health. A full-scale coking wastewater treatment plant with a two-stage anoxic-oxic-anoxic-oxic (A1/O1/A2/O2) process was investigated systematically. The experimental results showed that the AOAO process exhibited an excellent removal capacity of COD, ammonia, nitrate, and total nitrogen. The GC × GC-TOF MS analysis investigated that the majority of refractory organic compounds, such as phenols, quinolines, polycyclic aromatic hydrocarbons, hydrocarbons, etc., were either fully decomposed or exhibited significant decreases in concentration during the full-scale AOAO process, which offered insights to the biodegradation dynamics of CWW organic components. Microbial community analysis showed that bacterial communities were remarkably altered in the four bioreactors of the AOAO process: Proteobacteria dominated during the whole AOAO process, while Nitrospirae and Bacteroidetes enriched in the primary and secondary AO process, respectively. Moreover, metagenomic sequencing found that the relative abundances of amino acid metabolism and carbohydrate metabolism in the primary AO process were both higher than that in the secondary AO process. It indicated that as the AOAO process progressed, the changes in operational characteristics could remarkably affect the variations of functional microorganisms responsible for organics and nitrogen removal and metabolic functions of microbial community. Through this study, a comprehensive assessment of the AOAO biological processes of coking wastewater treatment was achieved, which provided valuable insights to the operation and evaluation of relevant real treatment plants.

The role of cation and the influence of the cation alkyl chain length of vinylimdazolium-based ionic liquid (IL) were studied previously to develop high-performance shale inhibitor for application in water-based drilling fluids (WBDFs). Results demonstrate that they have a considerable effect on the inhibition performance. However, the physicochemical properties can be tuned by changing the cation/anion combination. Therefore, the influence of anion type on the inhibiting performance must be investigated. In this study, we selected several vinylimdazolium-based ILs with different anions, such as bromide (Br−), tetrafluoroborate (BF4−), hexafluorophosphate (PF6−), and bis(trifluoromethylsulfonyl) (TFSI−). The size, solubility, hydrophilicity, and interaction in-between were tuned accordingly by changing the anion species. Results from linear swelling height, hot rolling recovery, and rheological measurements show that the IL with bromide anion has the most outstanding shale inhibiting performance. The anions influence the inhibitory performance of ILs in a distinct manner from cations by measuring the properties of Na–Bent dispersions added with different anion-based ILs. The former produces different abilities to suppress electric double layers and decreases the interlayer distance, whereas the latter mainly affects the interlayer distance. Despite different hydrophilic/hydrophobic properties, they have similar performance to inhibit the crystalline hydration and swelling. This condition is probably because they have a common cation that dominates the process of entering the interlayer void and narrowing interlayer spacing. Many hydrophilic ILs with anion Br− or BF4− have the capacity to strongly resist the repel interaction between clay particles and prompt aggregation, leading to better inhibitory performance. Combined with the previous result, cations and anions affect the IL inhibiting ability although their underlying mechanism is different. Thus, this work explored the relationship between inhibiting performance and IL moiety. The findings provide consolidate theoretical foundation for developing shale inhibitors for WBDFs.

Sludge composting is increasingly adopted due to its end product for application as a soil nourishment amendment. Although the ratio of C/N is significant in the quality and process of composting, little information has been obtained from the effects of nutritional energy (carbon and nitrogen) on the fate of antibiotic resistance genes (ARGs) during sludge composting. Dynamic variations of ARGs, microbial community as well as functional characteristics during composting of sludge were investigated in this study. Three levels of carbon to nitrogen (20:1, 25:1 and 30:1) were developed for the composting of sludge with fermented straw plus a control which was just sewage sludge (C/N = 9.5:1). A novel finding of this work is that the highest initial C/N ratio (30:1) could prolong the thermophilic period, which was helpful to reduce some target ARGs. Some ARGs (sul1, sul2, and aadA1) had negative correlation with multiple metabolic pathways, which were difficult to remove.

With the implementation of new domestic garbage classification policy in China, attention is growing to improve the treatment efficiency of municipal ‘wet’ waste. Combing with the new regulation, the synergistic strategy and the microbial ecology of the anaerobic co-digestion (AcoD) of cooked food waste (CFW), uncooked food waste (UCFW) and rice straw (RS) were analyzed in current study. Results showed that the maximum cumulative methane yield (CMY) and synergic index were obtained when CFW and UCFW were mixed at the ratio of 1:1 (based on volatile solid content). The highest CMY 452.94 ± 0.99 mL/g-VS was obtained when the ratio of CFW, UCFW and RS was 0.81:0.09:0.10, which was 16.29%, 36.20% and 121.84% higher than their mono-digestion, respectively. The AcoD promoted the methane potential by prolonging the release time of organic matter and slowing down the hydrolysis rate. Furthermore, the AcoD increased the species diversification and relative abundance of fermentation bacteria in digesters, and Methanosaeta predominated the methanogen communities. This study demonstrated a clean and sustainable AcoD strategy for safe disposal of urban food waste and revealed the variation of microbial community, which can provide a base for efficient bioenergy recovery from urban domestic garbage.

The design and performance of a near-infrared Raman imaging microscope (NIRIM) is described. This new instrument utilizes fiber-bundle image compression (FIC) to collect simultaneously a 3-D Raman spectral imaging data cube. Key NIRIM design features are discussed, including the FIC fiber-bundle, excitation laser, optical coupling to the microscope and fiber-bundle, holographic filtering, spectrograph imaging requirements, CCD parameters and chemical image processing. The theoretical collection efficiency and image quality of the NIRIM instrument are compared with those of tunable filter and line scanning Raman imaging methods. The performance of the NIRIM is demonstrated using a white light image of a bar-target and Raman chemical images of samples containing fructose–sucrose and Pb(NO3)2–K2SO4 microcrystalline mixtures. A Raman image collection time as fast as 1 s (total detector integration time) is demonstrated, for a 3-D data cube containing 322 image resolution elements and 900 Raman shift wavelengths. Copyright © 1999 John Wiley & Sons, Ltd.

A Raman probe was set up with optical fibers and a graded refractive index (GRIN) lens. It was found that the Raman background arising from optical fiber was spatially dependent, while normal Raman (NR) scattering, surface-enhanced Raman scattering (SERS), and surface-enhanced resonance Raman scattering (SERRS) were spatially independent. Spatial optimization was carried out to minimize the background interference of the optical fiber Raman probe with the use of benzoic acid as a test sample. The best configuration of the probe could also be applied to both SERS and SERRS. SER spectra of p-nitrophenol (1.0 × 10−3 M) and SERR spectra of methyl red (1.0 × 10−6 M) were obtained with the use of this probe to check its performance.