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Life cycle assessment of recycling rare earths from waste fluorescent powders was conducted, including the uncertainty and sensitivity analyses. Three scenarios were set in this study, namely, recycling with/without final disposal and waste fluorescent powders landfill. Recycling with final disposal presented lower environmental burden than that without final disposal due to the significant reduction of direct emissions. The evident impacts from chemicals and energy production stages were considered the main contributors to the overall environmental burden of recycling with final disposal due to their relatively high emissions of particulates matter, sulfur dioxide, heavy metals, and carbon dioxide as well as the use of fossil fuel. Compared with landfills, rare-earth recycling shows the highest environmental benefits because of the substitution of primary rare earths. To relieve the high demand of rare earths and reduce the overall environmental burden, governments are highly recommended to increase recycle rate, create a complete management system, improve energy consumption and wastewater treatment efficiency, and build an adequate recycle standard.

Straw pulp in China, which is the world's largest producer of this material, suffers from water and energy shortages during its entire life cycle. However, limited systematic studies have focused on these issues, and decision makers need be provided with improvement methods for the environmental performance. Thus, an impact-oriented energy and carbon coupled water footprint analysis was conducted in this study based on ISO standards. Results showed that the impact of energy consumption and carbon emissions exceeded that of water footprint. Carcinogens, non-carcinogens, and freshwater ecotoxicity also played effective roles in improving the environmental performance. Optimizing key indirect processes, including chemicals production, steam preparation, electricity generation, wood pulping, and fertilizer recovery, dominated the reduction in environmental burdens. Direct freshwater consumption and wastewater disposal played additional effective roles in controlling water footprint. The water network was thus optimized by a water pinch analysis to decrease the freshwater consumption and pollutant emissions by maximum values of 91.5% and 99.7% after optimization, respectively. Meanwhile, carbon dioxide, methane, chromium, arsenic, mercury, titanium, copper, strontium, total nitrogen, total phosphorus, BOD5, and COD were the main pollutants. Overall, the environmental impact can be further reduced by diminishing coal power ratio in national energy structure, adopting recovered steam, and considering multistage regeneration water network to cope with different water use demands.

In this paper, in order to enhance the thermal performance of sodium acetate trihydrate (SAT) in thermal storage, novel composite phase change materials (CPCMs) that contains SAT (as PCM) and silicon carbide (SC), bentonite (as additives) were prepared. The microstructures, chemical structures, leakage performances, phase change properties, thermal stability and thermal energy storage performances of the CPCMs were investigated. The experimental results indicate that the bentonite is helpful to solve the leakage problem. The supercooling phenomenon and thermal conductivity of SAT are improved by adding SC. In addition, compared with those of pure SAT, the heat storage time and release time of SAT/bentonite/SC CPCMs are shorten by 25.44% and 78.5% respectively when the mass fractions of bentonite and SC of the CPCMs are 26 wt.% and 10 wt.%. The research results exhibit a reference value for improving the thermal performance of SAT in thermal energy storage process.

Development of adventitious roots (ARs) at the base of the shoot is an important adaptation of plants to waterlogging stress; however, its physiological mechanisms remain unclear. Here, we investigated the regulation of AR formation under waterlogged conditions by hormones and reactive oxygen species (ROS) in Cucumis sativus L., an agriculturally and economically important crop in China. We found that ethylene, auxin, and ROS accumulated in the waterlogged cucumber plants. On the other hand, application of the ethylene receptor inhibitor 1-methylcyclopropene (1-MCP), the auxin transport inhibitor 1-naphthylphthalamic acid (NPA), or the NADPH oxidase inhibitor diphenyleneiodonium (DPI) decreased the number of ARs induced by waterlogging. Auxin enhanced the expression of ethylene biosynthesis genes, which led to ethylene entrapment in waterlogged plants. Both ethylene and auxin induced the generation of ROS. Auxin-induced AR formation was inhibited by 1-MCP, although ethylene-induced AR formation was not inhibited by NPA. Both ethylene- and auxin-induced AR formation were counteracted by DPI. These results indicate that auxin-induced AR formation is dependent on ethylene, whereas ethylene-induced AR formation is independent of auxin. They also show that ROS signals mediate both ethylene- and auxin-induced AR formation in cucumber plants.

Coal-to-olefin (CTO) projects, an energy strategy, are increasing in number in China but suffer from high consumption and pollution. In this study, a life cycle assessment is studied to determine whether oil field gas-assisted CTO systems have the potential to solve these problems. Oil-to-olefin is presented for comparison. Results showed that the current CTO scenario generally exerts a higher environmental impact than oil-to-olefin. The effects on carcinogens, climate change, and fossil depletion, which were provided mainly by chromium to water, carbon dioxide to air, and hard coal consumption, respectively, are the main contributors to the environmental burden. Oil field gas-assisted coal-to-methanol production decreases the potential impact on climate change, carcinogens, and fossil depletion by 40%, 9%, and 50%, respectively, because it consumes less coal (>73%) than conventional coal-to-methanol production. Oil field gas-assisted CTO is an attainable and effective means of carbon reduction in the CTO industry in China. It is highly recommended for further improving the environmental performance of the CTO industry.

Biolubricants do not cause the environmental pollution resulting from the manufacturing and use of mineral-based lubricants, but the commonly adopted chemical method of preparing biolubricants using expensive vegetable oils as raw materials is still environmentally and economically unsatisfactory. In this study, R. glutinis lipid with a high oleic-acid content was esterified with trimethylolpropane (TMP) by using the Candida sp. 99–125 enzyme in a solvent-free system, and the effect of the microbial oil with the high oleic-acid content on the performance of resulting biolubricants was investigated. The purpose of this study was to solve the problems of pollution caused by the chemical synthesis of biolubricants and of the uneconomical use of vegetable oils as raw materials. Further, this study aimed to improve the performance of biolubricants by using the microbial lipid with a high oleic-acid content. As a result of optimization of the reaction conditions, the yield of trimethylolpropane fatty acid triester (TFAT) reached 89.5%. The synthesized biolubricants had excellent low-temperature lubrication performance (pour point = − 45 °C), and the physicochemical performance reached the ISOVG-46 grade. The results of the high-frequency reciprocating friction test (HRFT) show that the products have better tribological properties than mineral-based lubricants of the same viscosity grade (friction coefficient = 0.085; average wear scar diameter = 187 µm).

In circulating water system, methyl benzotriazole (TTA) is one of the common corrosion inhibitors for copper. But the inhibition mechanisms have not been clearly understood so far. In different number of water molecules, the interaction between TTA and Cu2O (copper surface) was investigated with molecular dynamics (MD) method. The results showed that the MD simulation result with water was more consistent with the experiment results. In different number of water molecules, the sequence of the interaction energies between TTA and Cu2O (001) was ∆E1 (150H2O) > ∆E1(200H2O) > ∆E1(100H2O) > ∆E1(50H2O) > ∆E1(0H2O). The number of water molecules had an important influence on the interaction between corrosion inhibitors and Cu2O crystal. From non-bond energy and pair correlation functions, the interaction energies of the model system were mainly contributed by the non-bond interaction. Strong adsorption could be raised by the Coulomb interaction between the negatively charged functional groups in TTA and the positive copper ions in the Cu2O (001) face, and further interaction between aggressive media and copper could be restricted. So, copper corrosion could be avoided. Chemical bonds and non-bond interactions were formed between TTA and Cu2O (001) in different number of water molecules. Water molecules could not be ignored during the MD simulation, too. The results obtained here may provide theoretical supports for developing new corrosion inhibitors.

Utilizing halogens as traceless directing goups represents an attractive strategy for C-H functionalization. A two C-H alkylation system, initiated by the oxidative addition of organohalides to Pd0 , has been developed. The first reaction involves an intermolecular alkylation of palladacycles to form C(sp3 )-C(sp2 ) bonds followed by C(sp2 )-H activation/cyclization to deliver alkylated benzocyclobutenes as the final products. In the second reaction, two C-C bonds are formed by the reaction of palladacycles with CH2 Br2 , and provides a facile and efficient method for the synthesis of indanes. The alkylated benzocyclobutene products can be transformed into tricyclic hyrocarbons, and the indane derivatives are essential structural motifs in bioactive and odorant molecules.

Life cycle assessment was carried out via ReCiPe H method to evaluate environmental impact of the hydrometallurgical zinc production chain in China. National statistical data and process-based life cycle inventory (LCI) were used to build a zinc production LCI at the macro level. To confirm the credibility of this study, an uncertainty analysis was conducted via Monte-Carlo simulation. The impacts of climate change, human toxicity, marine ecotoxicity, freshwater ecotoxicity, metal depletion, and fossil depletion categories on the overall environmental burden were examined. The overall environmental burden was dominated by key processes, such as zinc ore mining and energy (i.e., electricity and natural gas) consumption. In 2013, the amounts of carbon dioxide, sulfur dioxide, nitrogen oxide, particulate matter, zinc, and copper generated by hydrometallurgical zinc production were 2.60 × 10 7 , 4.29 × 10 4 , 6.77 × 10 4 , 1.23 × 10 4 , 1.38 × 10 3 , and 3.20 × 10 2 t. The first four substances accounted for 0.25%, 0.21%, 0.30%, and 0.10% of the overall national emission. Effective approaches to reduce the overall environmental impact of hydrometallurgical zinc production include improving the efficiencies of electricity, natural gas, and zinc ore consumption; substituting clean energy for coal-based electricity production; reducing the direct emission of zinc and copper; and increasing the national zinc recycle rate.

The life cycle assessment of tungsten carbide powder production was conducted in this study using the updated ReCiPe method with the consideration of China’s environmental, geographic, and exposed situation. Uncertainty analysis was applied based on Monte-Carlo simulation to evaluate the variation range of the results. The environmental burdens were basically derived from carcinogens, freshwater ecotoxicity, climate change, and fossil depletion categories mainly because of the ammonium paratungstate hydrate production. Electricity consumption, sludge disposal to landfill, and direct water emissions from the tungsten ore mining and concentration process played dominant roles in the aforementioned process. Improving the ammonium paratungstate hydrate consumption efficiency, reducing mining loss rate, optimizing national power structure, increasing landfill-gas utilization rate, and controlling the pollutant emission from wastewater are the key factors that could reduce the overall environmental burdens generated by China’s tungsten carbide powder production.

High triglycerides (TG), low high-density lipoprotein cholesterol (HDL-C) and high non-HDL-C levels are risk factors for cardiovascular disease (CVD). It is unclear whether the combinations of their adverse changes are related with CVD risk in different gender and diabetes status, particularly in Chinese population. This study aims to evaluate the CVD risk associated with different adverse lipid combinations. A total of 38,989 participants from Chinese Multicenter Longitudinal Health Management Cohorts (mean age 42 years; 62% male) without baseline CVD were followed up for incident CVD from 2007 to 2015. Participants with various combinations of baseline TG, non-HDL-C, and HDL-C levels within- or out of range according to Adult Treatment Panel III were grouped into 8 distinct lipid categories. Cox models estimated the multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of different lipid categories for CVD. After multivariable adjustment, a low level of HDL-C combined with either a high level of non-HDL-C alone or TG alone were associated with increased CVD risk with adjusted HRs (95% CIs) of 1.77 (1.36 to 2.30) and 2.08 (1.30 to 3.34) in male participants. Diabetic participants with high non-HDL-C and low HDL-C levels (adjusted HR 2.93, 95% CI 1.15 to 7.46), and non-diabetic participants with high TG and low HDL-C levels (adjusted HR 1.73, 95% CI 1.33 to 2.26) had greater risk of incident CVD. These relations remained significant when limited analysis to participants with normal LDL-C levels of

Polyvinyl chloride (PVC), the second most widely consumed plastic, is a 21st century material generally used in pipes, cables, and other construction applications. Life cycle assessment (LCA) of polyvinyl chloride production and its recyclability in China was conducted to investigate the environmental impact generated from PVC industry. Uncertainty analysis was conducted using the Monte Carlo simulation. Results showed that the key materials contributing to the general environmental burden were chlorine, carbon dioxide, and nitrogen oxides for both scenarios. The primary PVC scenario had an overwhelmingly great environmental impact in most categories except for agricultural land occupation. The impact on climate change can be decreased by 36.21% and 15.53% respectively in producing 1 ton of primary PVC considering alternative energy sources, such as proportionally replacing coal-based electricity generation by hydropower and hybrid power according to the State Grid structure. The key factors in reducing the overall environmental impact of PVC production are promoting the use of recycled PVC, reducing NMVOC emissions, and raising the renewable energy ratio.

To high value-added utilization of waste polystyrene (PS) foam, an in-situ phase change material (PCM) encapsulation protocol was realized by using waste PS foam as a holding material for thermal energy storage with a shape-stabilization methodology. Mechanistic study suggested that the robust Lewis acid catalysed Friedel-Crafts reaction involved was the key to the success of this method owing to a simultaneous process of porous structure formation and PCM impregnation, by which the PCM encapsulation rate can attain to 68.7% without leakage. Lewis acid catalysts used in the process were able to be converted to their corresponding metal oxides via a simple alkali treatment, which not only diminished the tedious metal species isolation step but also made an external thermal conductivity enhancement that an utmost 61.0% thermal conductivity enhancement can be achieved compared with that of pristine paraffin wax. Additionally, the PCM composite preparation process can be facilely scaled up which strongly demonstrated its real application feasibility. Moreover, besides waste PS foam, other waste PS based materials were proven to be feasible towards PCM holding materials with the same approach.

The title compound, [Sr(C(10)H(6)NO(2))(2)(H(2)O)(2)](n), contains an eight-coordinate Sr(II) ion displaying a distorted square-anti-prismatic geometry, two quinoline-3-carboxyl-ate ligands and two terminal water mol-ecules. The Sr(II) atom is surrounded by six carboxyl-ate O atoms from four separate quinoline-3-carboxyl-ate ligands and two O atoms from two coordinated water mol-ecules. The bridging carboxyl-ate O atoms [Sr-O = 2.498 (3) and 2.495 (3) Å] link Sr(II) atoms, forming a chain substructure extending along the c axis. The chains are linked by O-H⋯N and O-H⋯O hydrogen bonds, giving a three-dimensional framework structure.

In the title complex, {[Na(C7H7N2O4)(H2O)2]·H2O}n, the NaI atom exhibits a distorted octa­hedral geometry and is six-coordinated in an NO5 environment. The equatorial plane is defined by three O atoms and one N atom from two distinct 5-carb­oxy-2-ethyl-1H-imidazole-4-carboxyl­ate (H2EIDC) ligands and one coordinated water mol­ecule, and the apical sites are occupied by one carboxyl O atom from one H2EIDC ligand and one O atom from the other coordinated water mol­ecule. The NaI atoms are linked by H2EIDC ligands, generating an infinite double chain along the a axis. These chains are further connected via O—H⋯O and N—H⋯O hydrogen bonds into a three-dimensional supra­molecular network.

Each of the carboxyl-ate -CO(2) fragments of the dianion ligand in the title compound, {[Sr(C(9)H(4)N(2)O(4))(H(2)O)(2)]·H(2)O}(n), chelates to a Sr(II) atom and at the same time, one of the two O atoms coordinates to a third Sr(II) atom. The μ(4)-bridging mode of the dianion generates a square-grid layer motif; adjacent layers are connected by O-H⋯O, O-H⋯N and N-H⋯O hydrogen bonds, forming a three-dimensional network. The eight-coordinate Sr atom exists in a distorted square-anti-prismatic geometry. The crystal studied was a non-merohedral twin with a minor twin component of 24%.

In the title complex, [Mg(C9H4N2O4)(H2O)2]n, the MgII atom is six-coordinated by one N and three O atoms from three different 1H-benzimidazole-5,6-dicarboxyl­ate ligands and two O atoms from two water mol­ecules, forming a slightly distorted octa­hedral geometry. The ligand links the MgII centres into a three-dimensional network. Extensive N—H⋯O and O—H⋯O hydrogen bonds exist between the ligands and water mol­ecules, stabilizing the crystal structure.