Search

Hydrogen sulfide is characterized with strong toxicity and corrosivity, so it is important to efficiently minimize its pollution. In this laboratory experiment a series of HPAs@UiO-66 were prepared by one-step hydrothermal method with molybdenum-based heteropoly acid (HPAs) as active centers and UiO-66 as a carrier, and a multi-acid-based solid phase desulfurization system with various active centers was set up. The effects of Keggin and Dawson structures, the central atoms (P and Si), and the substitutional atoms (V and W) of HPAs on desulfurization performance were studied, and their physico-chemical properties were analyzed by BET, FT-IR, XRD, SEM, and TEM. As a result, it was showed that PMo12@UiO-66 had excellent desulfurization activity, its H2S removal ability was maximized at 100 °C with a absorbing capacity being able to reach 17.18 mg/g, and it was found the presence of water in the mixed gas can promote PMo12@UiO-66 to remove H2S. In comparison with PMo12 and UiO-66, PMo12@UiO-66 was far better in desulfurization, its H2S absorbing capacity was 7.5 and 14.2 times PMo12 and UiO-66, respectively, demonstrating the synergistic desulfurization effect of PMo12 and UiO-66. Analysis by use of XPS (X-ray photo-electron spectroscopy) showed that the redox reaction took place between PMo12 and H2S, during which H2S was converted into elemental sulfur due to the oxidizing action of PMo12. In conclusion, this study proved that the introduction of PM012 had exhibited the most remarkable effect on enforcing the desulfurization performance of UiO-66, which could provide a reference for exploiting more novel HPA-based solid phase desulfurization agents. [ABSTRACT FROM AUTHOR]

Coherence is intrinsically related to projective measurement. When the fixed projective measurement involves higher-rank projectors, the coherence resource is referred to as block coherence, which comes from the superposition of orthogonal subspaces. Here, we establish a set of quantitative relations for the interconversion between block coherence and multipartite entanglement under the framework of the block-incoherent operations. It is found that the converted multipartite entanglement is upper bounded by the initial block coherence of single-party system. Moreover, the generated multipartite entanglement can be transferred to its subsystems and restored to block coherence of the initial single-party system by means of local block-incoherent operations and classical communication. In addition, when only the coarse-grained quantum operations are accessible for the ancillary subsystems, we further demonstrate that a lossless resource interconversion is still realizable, and give a concrete example in three four-level systems. Our results provide a versatile approach to utilize different quantum resources in a cyclic fashion.

With the rapid development of e-commerce and express delivery industries, a large number of waste plastic express packaging bags (WPEPBs) are generated and urgent to be safely disposed. In this work, a novel resource conversion strategy was developed to produce high value-added chemicals from WPEPBs by supercritical water ammonia (SWA) process without any catalyst. WPEPBs could be converted into two parts by the SWA process: oil and solid residue. More than 80 % of the oil was identified as long-chain alkanes and alkenes due to the decomposition of polyethylene (PE) contained in WPEPBs. The presence of NH 3 in SWA was beneficial to improve the production of long-chain alkenes. The plasticizers in WPEPBs including bisphenol A (BPA) and phthalate ester (DEHP) could be efficiently converted into aniline (≈15%) and 2-ethylhexanol (≈4 %) due to the high reactivity of NH 3 in the SWA process. Compared with the degradation of WPEPBs in supercritical water, the SWA process could reduce side effects and improve the purity of target products. High-purity CaCO 3 powder could be further recovered from the solid residue. The optimal parameters of the SWA process for the conversion of WPEPBs by Response Surface Methodology (RSM) were 440.5 ℃, 90 min, and C NH3 of 4.8 wt%. The conversion ratio of WPEPBs (C WPEPBs) and CaCO 3 recovery ratio (R CaCO3) were 99.10 % and 98.85 %, respectively. In contrast to traditional methods for recycling of plastic waste such as mechanical recycling and incineration, the SWA process is believed to be a clean and high-efficiency resource conversion strategy for WPEPBs. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, the diversity of microbial consortium coming from a shale gas well was initially analyzed by 16 S full length sequencing, and the primary bacteria are Arciella (53.37 %), Shewanella (43.61%), and Desulfovibrio (1.95 %). These bacteria can produce large amounts of H 2 S using sulfate as electron acceptor. Subsequently, microbiologically influenced corrosion (MIC) behavior and MIC inhibition mechanism of norfloxacin and clindamycin hydrochloride are studied. The bacteria in anaerobic microbial consortium (AMC) significantly accelerate steel corrosion, but norfloxacin and clindamycin hydrochloride both can effectively inhibit MIC at a low concentration (40 mg/L) with inhibition efficiencies of 85.2 % and 82.7 %, respectively. [Display omitted] • A good method to solve the potential risks of obsolete antibiotics is proposed based on the strategy of resource conversion. • The primary bacteria are Arciella (53.37 %), Shewanella (43.90 %), and Desulfovibrio (1.95 %) in a shale gas produced water. • Desulfovibrio is not the chief bacterial in this environment. • The bacteria in anaerobic microbial consortium (AMC) significantly accelerate steel corrosion. • Norfloxacin and clindamycin hydrochloride both can effectively inhibit MIC caused by AMC at a low concentration (40 mg/L). [ABSTRACT FROM AUTHOR]

[Display omitted] • A nontoxic metal-free carbon dot/g-C 3 N 4 composite photosensitizer was fabricated. • Novel visible-light-driven antimicrobial films were successfully constructed. • Incorporated carbon dot/g-C 3 N 4 improved the physicochemical properties of the films. • The "fresh-like" characteristics of bananas were effectively maintained. A novel carbon dot/g-C 3 N 4 nanocomposite (CCN) exhibiting enhanced photocatalytic activity was developed and used as a photoactive nanofiller to construct corn starch/carboxymethyl cellulose (CS/CMC)-based functional films. The morphologies and structures of the CCN-CS/CMC composite films were investigated with scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction. The effects of the CCN on the physicochemical properties and antibacterial activities of the films were analyzed. The properties of the films were optimized with the addition of CCN (0.20 mg/mL), and the tensile strength of the film was increased to 11.9 MPa and the water contact angle was increased to 103.39°. The optimal active film showed > 99.9 % antibacterial efficiencies against Escherichia coli and Staphylococcus aureus under visible light and prolonged the shelf lives of bananas for more than four days compared to the 4-day shelf life of the control. This work provides a novel route for developing antimicrobial active packaging. [ABSTRACT FROM AUTHOR]

COVID-19 pandemic has affected the fabric of the world: health system, travel, living and working styles, and economy. Furthermore, it has also severely impacted the previously on-going global efforts to reduce the use of plastic waste. During the period of the whole COVID-19, the sustainable measures and products adopted for the conservation of our land and marine ecosystem are being neglected or at the very least, kept on hold. The use of plastic-based personal protective equipment (PPEs) and sanitizers by health-care professionals and the public has led to a huge surge in a plastic waste generation without any plans to mitigate its severity. It is vital to understand the impact of this problem and find the possible solutions. The sudden escalation in medical plastic waste makes it difficult to follow the protocol of medical plastic waste handling in the civic waste management system. In this article all plastic waste management issues faced globally, especially in the developing world, have been highlighted. Moreover, in the end, some possible solutions have been recommended for the safe handling of plastic wastes in the civic society such as plastic waste management system, the use of artificial intelligence from generation to disposal, etc. In addition, the steps to produce a zero waste society have been recommended. This study emphasizes not only government institutes and technological centers but also on the common citizens to make a sustainable civic society. [ABSTRACT FROM AUTHOR]

In this study, a novel renewable hybrid system was designed and constructed to efficiently produce biodiesel through various methods. First, a parabolic trough solar collector (PTC) was used as a renewable source for producing desalinated water in a solar still. Then, the heat dissipated by PTC and water produced by the solar still were used to generate biodiesel. Finally, the combined cycle of PTC/desalination/biodiesel generator was applied to produce heat and steady power. Necessary electricity in the hybrid system containing pumps, mixing tools, etc. was provided by photovoltaic panels. After launching the hybrid system and performing experiments to produce biodiesel on Palm and Chlorella bioenergy carriers, the percentage of the biodiesel production for these two species in different ways were as follows: alkaline catalyzed transesterification (79.17,81.46), acid-catalyzed transesterification (79.1,81.43), two-step transesterification (78.07,81.42), supercritical transesterification (75.16,80.68), microemulsion (76.3,81.4), electrolysis (50.25, 58.87), and pyrolysis (13.677,14.833). Moreover, the lowest price belonged to the alkaline catalyzed transesterification which for palm/ chlorella was 0.65/0.972. In most methods, the cetane number of palm-based biodiesel was higher (∼58). Consequently, it had a better combustion quality compared to chlorella-based biodiesel (∼44). This study also modeled various processes for the bioenergy carrier conversion. The results were consistent with experimental data. • Simultaneous application of solar/hydro/biomass renewable resources. • Introduction of a novel set of PV/PTC/SSD/BG renewable hybrid system. • Achievement of biomass conversion and power production by a renewable hybrid system. • Reaching higher biodiesel's yield and lower production cost by a modified PTC. • Modeling of all conversion methods were modeled where possible. [ABSTRACT FROM AUTHOR]

[Display omitted] • The resource conversion of citrus peel (CP) biowaste was effectively realized. • A novel metal- and additive-free CP-derived CDs/g-C 3 N 4 composites were synthesized. • CP-derived CDs/g-C 3 N 4 showed enhanced photodegradation performance for SY removal. • The photodecomposition method exhibited excellent reusability and biosafety. In this study, novel, metal-free, CP-derived CDs/g-C 3 N 4 nanocomposites (CDCNs) were created by introducing citrus peel-derived carbon dots (CP-derived CDs) into graphite carbon nitride (g-C 3 N 4) by a green hydrothermal method. The CDCNs were revealed to have superior photoelectrochemical properties relative to pristine g-C 3 N 4 for the photocatalytic degradation of the food dye sunset yellow (SY) under visible light. For SY decomposition, the recommended catalyst contributed almost 96.3% to the photodegradation rate after 60 min of irradiation, showing satisfactory reusability, structural stability and biocompatibility. Moreover, a mechanism for enhanced photocatalytic SY degradation was proposed according to band analysis, free radical trapping and electron paramagnetic resonance (EPR) results. A possible pathway for SY photodegradation was also predicted from UV–visible (UV–Vis) spectroscopy and high-performance liquid chromatography (HPLC) results. The constructed nonmetallic nanophotocatalysts afford a novel route for the elimination of harmful dyes and for the resource conversion of citrus peels. [ABSTRACT FROM AUTHOR]

Improvements in networking technologies have provided users with useful information services. Such information services may bring convenience and efficiency, but might be accompanied by vulnerabilities to a variety of attacks. Therefore, a variety of research to enhance the security of the systems and get the services at the same time has been carried out. Especially, research on intrusion-tolerant systems (ITSs) has been conducted in order to survive against every intrusion, rather than to detect and prevent them. In this paper, an ITS based on effective resource conversion (ERC) is presented to achieve the goal of intrusion-tolerance. Instead of using the fixed number of virtual machines (VMs) to process requests and recover as in conventional approaches, the ITS based on ERC can transform the assigned resources depending on the system status. This scheme is proved to maintain a certain level of quality of service (QoS) and quality of security service (QoSS) in threatening environments. The performance of ERC is compared with previous studies on ITS by CSIM 20, and it is verified that the proposed scheme is more effective in retaining a specific level of QoS and QoSS.

[Display omitted] • A novel macrocycle-confinement pyrolysis strategy was proposed. • MoN 2 @NPC catalyst was first applied in heterogeneous removal systems for H 2 S. • Synergistic effect between MoN 2 and NPC promoted efficient desulfurization. • The durable removal and conversion of H 2 S can be maintained for >100 h. • The desulfurization product was proved as S 8. The efficient removal of H 2 S is significant to the chemical industry and environmental protection. In this study, a macrocycle-confinement pyrolysis strategy was explored to synthesize a confined MoN 2 @N-rich porous carbon (MoN 2 @NPC) catalyst using β-cyclodextrin encapsulating phosphomolybdic acid (PMo 12 ⊂ β-CD) as a Mo precursor to improve the desulfurization activity of carbonaceous catalysts for the efficient conversion of H 2 S to sulfur. The decomposition of PMo 12 ⊂ β-CD not only generated well distributed MoN 2 sites, but also enriched pore structures due to the pore-forming ability of β-CD. MoN 2 @NPC possessed a high breakthrough capacity of 173.9 mg/g at room temperature and excellent durability (>100 h) at 200 °C toward continuous H 2 S selective oxidation. Furthermore, MoN 2 @NPC showed a remarkable superiority to common catalysts (PC, NPC, and MoN 2 -NPC), revealing the effectiveness of the macrocycle-confinement pyrolysis strategy for strengthening desulfurization activity. The excellent desulfurization ability of MoN 2 @NPC was attributed to the synergetic effect of uniform MoN 2 sites and N species (pyridinic N and pyrrolic N). Additionally, the formed water film and activated O 2 on MoN 2 @NPC further induced H 2 S dissociation and oxidation. This work provides a key insight into the behavior of H 2 S oxidative removal over NPC-based catalysts and offers a promising route to construct non-precious catalysts with high desulfurization activity. [ABSTRACT FROM AUTHOR]

Tetrabromobisphenol A epoxy resin (TBBPA-ER) is the most important nonmetallic composition of waste printed circuit boards (PCBs). Currently, the TBBPA-ER waste is mainly sent to incineration or landfills. The great obstacle of the recovery of the TBBPA-ER waste is the low value-added products obtained by existing technologies. In this study, a novel resource conversion strategy was developed to produce high-purity phenolic chemicals from the TBBPA-ER waste by subcritical water-CuO (SubCW-CuO) process. The high selectivity of the SubCW-CuO process for the recovered products from the TBBPA-ER waste could be attributed to the regulating effect of CuO. The CuO could preferentially trigger the rupture of C-O and C-Ph bonds in the TBBPA-ER chain, resulting in the producing of high-purity phenol (91.47 %) at 300 °C. The reaction between phenol and methyl radical (derived from β-scission of ternary carbon chain groups in the TBBPA-ER waste) resulted in the recovery of high-purity p-cresol (90.30 %) at 350 °C. The optimal conditions of the SubCW-CuO process were solid-liquid ratio of 1:30 g/mL, M(TBBPA-ER):M(CuO) ratio of 10:1 g/g, and 60 min. The conversion ratio of the TBBPA-ER waste could reach 70 % under the optimal conditions. Approximately 3 % of the bromine was transferred into the oil phase products after the SubCW-CuO process at 250 °C, while no organic bromine could be found in the oil phase products at 300 and 350 °C. More than 70 % of the bromine was fixed in the solid residue after the SubCW-CuO process at 300 and 350 °C. The bromine contained in the solid residue mainly existed in the form of CuBr and the Cu species had efficient capture ability for the bromine released from the molecular chain of the TBBPA-ER. It is believed that the SubCW-CuO process developed in this study is a promising alternative technology for the high-efficiency resource conversion of the TBBPA-ER waste. [Display omitted] • We report a novel resource conversion strategy of TBBPA-ER waste by SubCW-CuO. • CuO could catalyze and regulate the conversion reaction of TBBPA-ER waste in SubCW. • High-purity phenol (91.47 %) and p-cresol (90.30 %) could be obtained from TBBPA-ER. • The reaction parameters were optimized and the conversion mechanism was proposed. [ABSTRACT FROM AUTHOR]

Recent evidence suggests that special interest groups significantly affect tropical deforestation through lobbying. We develop an open-economy model in which resource conversion is determined by a self-interested government that is susceptible to the influences of the political contributions it receives from the profit-maximizing economic agent responsible for land conversion. We investigate the effects of lobbying on the cumulative level of resource conversion and examine how trade policy influences the distortions created by political corruption. We derive testable predictions that are analyzed through a panel analysis of cumulative agricultural land expansion over 1960-99 for low and middle-income tropical countries. Our findings suggest that increased corruption and resource dependency directly promote land conversion, whereas rising terms of trade reduce conversion. [ABSTRACT FROM AUTHOR]