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The presence and detection of hazardous environmental gases at deficient concentrations are essential to protect human beings from intensive gas exposures. Therefore, the development of high-response gas sensors is vital to overcome these overwhelming issues. The spherical In2O3 nanoparticles are successfully decorated onto ZnO nanosheets in ZnO@In2O3 (ZIO) nanocomposites via a simple co-precipitation method. The as-prepared nanocomposites are exposed to gas-sensing applications. The fabricated gas sensors exhibit high sensing response and selectivity towards NO2 gas than other gases, tested at various working temperatures and different range of gas concentrations. The gas-sensing property of ZnO nanosheets and ZIO nanocomposites has been investigated, which reveals that 10 wt% ZIO nanocomposites shows the outstanding response of 68 at 70 ppm (1.88% higher than pristine ZnO NSs), possesses fast response/recovery time (43, 65 s) respectively, and demonstrates excellent stability and repeatability. A plausible nanostructure formation and gas-sensing mechanism are also discussed in detail. The fabricated sensors are considered potential applicants in the development of the NO2-based gas sensor industry. [ABSTRACT FROM AUTHOR]

The method of fluorescent probes has been an important technique for detection of nitrite (NO2−). As an important inorganic salt, excessive nitrite would threaten humans and the environment. In this paper, a colorimetric fluorescent probe P‐N (1,2‐diaminoanthraquinone) with rapid response and high selectivity, which could detect NO2− by visual colour changes and fluorescence spectroscopy is presented. The probe P‐N solution (pH 1) changed from pink to colourless with the addition of NO2− and fluorescence intensity at 639 nm clearly decreased. Good linear exists between fluorescence intensities and NO2− concentrations for the range 0–16 μM, and the detection limit was 54 nM (based on a 3σ/slope). Moreover, probe P‐N could also detect NO2− in real water samples, and results were all satisfactory. Probe P‐N shows great practical application value for detecting NO2− in the environment. [ABSTRACT FROM AUTHOR]

Encouraging the adoption and diffusion of low-carbon agricultural technology innovation is an important measure to cope with climate change, reduce environmental pollution, and achieve sustainable agricultural development. Based on evolutionary game theory, this paper establishes a game model among agricultural enterprises, government, and farmers and analyzes the dynamic evolutionary process and evolutionary stable strategies of the major stakeholders. The impact of innovation subsidies, carbon taxes, and adoption subsidies on low-carbon agricultural innovation diffusion is simulated using Matlab software. The results show that the government's reasonable subsidies and carbon taxes for agricultural enterprises and farmers can increase the enthusiasm of agricultural enterprises and farmers to participate in low-carbon agriculture. This study can be used as a basis for the government to formulate more targeted policies to promote the diffusion of low-carbon agricultural innovation. [ABSTRACT FROM AUTHOR]

A new compound, ethyl 5‐phenyl‐2‐(p‐tolyl)‐2H‐1,2,3‐triazole‐4‐carboxylate was successfully introduced and synthesized as a novel rhodamine B derivative named REPPC, and characterized by 1H nuclear magnetic resonance (NMR), 13C NMR, and high resolution mass spectrometry (HRMS). It showed an obvious fluorescence and UV–visible light absorption enhancement towards Hg2+ ion without interference from common metal ions in N,N‐dimethylformamide–H2O (pH 7.4). The spirolactam ring moiety of rhodamine in REPPC was converted to the open‐ring form generating a 1:1 complex with the intervention of a mercury ion, verified by electrospray ionization‐mass spectroscopy testing and density functional theory calculation. REPPC was used to visualize the level of mercury ions in living HeLa cells with encouraging results. [ABSTRACT FROM AUTHOR]

Industrial manufacturing of ethylene chlorohydrin (ECH) critically requires excess corrosive hydrochloric acid or hypochlorous acid with dealing with massive by-products and wastes. Here we report a green and efficient electrosynthesis of ECH from ethylene oxide (EO) with NaCl over a NiFe 2 O 4 nanosheet anode. Theoretical results suggest that EO and Cl preferentially adsorb on Fe and Ni sites, respectively, collaboratively promoting the ECH synthesis. A Cl radical-mediated ring-opening process is proposed and confirmed, and the key Cl and carbon radical species are identified by high-resolution mass spectrometry. This strategy can enable scalable electrosynthesis of 185.1 mmol of ECH in 1 h with 92.5 % yield at a 55 mA cm -2 current density. Furthermore, a series of other chloro- and bromoethanols with good to high yields and paired synthesis of ECH and 4-amino-3,6-dichloropyridine-2-carboxylicacid via respectively loading and unloading Cl are achieved, showing the promising potential of this strategy., (© 2023 Wiley-VCH GmbH.)

In view of the particularity and high risk of coal mining industry, the decision-making behavior of multiple agents inside the coal-mine enterprise plays a very important role in ensuring the safety and sustainable development of coal mining industry. The existing literature studies on coal-mine safety production focus mainly on statically analyzing the game among the external entities such as the government, the enterprises themselves, and the employees inside the enterprise from a macro perspective,are short of research on revealing the dynamic interactions among the actors directly involved in the coal-mine accidents and also on proposals for effective interactions that will lead to improved safety outcomes. Therefore, this paper explores the use of evolutionary game theory to describe the interactions among the stakeholders in China's coal-mine safety production system, which includes the organization, the first-line miners, and the first-line managers. Moreover, the paper also explores dynamic simulations of the evolutionary game model to analyze the stability of stakeholder interactions and to identify equilibrium solutions. The simulation results show that when certain conditions are met, the decision-making behavior of the organization, miners, and managers can evolve into the unique ideal steady state (1, 1, 1). In addition, the strategy portfolio with a relatively high initial proportion of three agents converges more quickly to an ideal state than a relatively low strategy portfolio. Moreover, the stable state and equilibrium values are not affected by the initial value changes. Finally, we find that the combination of positive incentive policies and strict penalties policies can make the evolutionary game system converge to desired stability faster. The application of the evolutionary game and numerical simulation when simulating the multiplayer game process of coal-mine safety production is an effective way, which provides a more effective solution to the safety and sustainable development of coal mining industry. [ABSTRACT FROM AUTHOR]

Highlights: Operations of metal oxide semiconductors gas sensors at room temperature under photoactivation are discussed. Emerging two-dimensional (2D) materials-based gas sensors under light illumination are summarized. The advantages and limitations of metal oxides and 2D-materials-based sensors in gas sensing at room temperature under photoactivation are highlighted.Room-temperature gas sensors have aroused great attention in current gas sensor technology because of deemed demand of cheap, low power consumption and portable sensors for rapidly growing Internet of things applications. As an important approach, light illumination has been exploited for room-temperature operation with improving gas sensor’s attributes including sensitivity, speed and selectivity. This review provides an overview of the utilization of photoactivated nanomaterials in gas sensing field. First, recent advances in gas sensing of some exciting different nanostructures and hybrids of metal oxide semiconductors under light illumination are highlighted. Later, excellent gas sensing performance of emerging two-dimensional materials-based sensors under light illumination is discussed in details with proposed gas sensing mechanism. Originated impressive features from the interaction of photons with sensing materials are elucidated in the context of modulating sensing characteristics. Finally, the review concludes with key and constructive insights into current and future perspectives in the light-activated nanomaterials for optoelectronic gas sensor applications. [ABSTRACT FROM AUTHOR]

Food safety accidents occur frequently, which has caused great harm to people's health. With the consideration that food quality requires the joint efforts of all members of the food supply chain and that quality-improving efforts for food have a positive external effect, we focus on the quality-improving effort level, which is very important for food quality and safety. This paper builds an evolutionary game model and employs the replicated dynamic equation to study evolutionarily stable strategies of suppliers and producers. Furthermore, simulation experiments are conducted to verify the modeling analyses and demonstrate the influences of game parameters. The research results show that the behavioral strategies are closely related to the factors such as the ratios of the input to the output, the cost of quality-improving efforts, the hitchhiking benefits, and the initial strategy. Only when the punishing dynamics of the government exceeds a certain value, both participants can choose the quality-improving effort strategy. Based on the results, this paper has provided some inspiration for policy-making of government institutions. [ABSTRACT FROM AUTHOR]

A novel two-dimensional Cd-based metal–organic framework, {[Cd(Hcpnc)(DMF)]·DMF·2H2O}n (Cd-MOF) has been synthesized successfully under solvothermal conditions by utilizing a multifunctional N,O-building block ligand, 2-(2,5-dicarboxylphenyl)nicotinic acid (H3cpnc), which is a new and virtually unexplored multifunctional pyridine-tricarboxylic building block. The product was isolated as a stable crystalline solid and was fully characterized by IR spectroscopy, elemental analyses, thermogravimetry and differential scanning calorimetry, powder X-ray diffraction, single-crystal X-ray diffraction analyses, and X-ray photoelectron spectroscopy. The solid-state luminescence properties of the Cd-MOF were studied at ambient temperature. The compound shows high selectivity and sensitivity for Cu2+ ions and nitrobenzene by the luminescence quenching behavior with excellent repeatability. Additionally, the Cd-MOF exhibits an excellent specific capacitance of 321 F g−1 at 0.5 A g−1 and it still retains 95.2% of the original capacitance after 1000 cycles. Therefore, the Cd-MOF as a kind of bifunctional material will have broad application prospects in luminescence detection and supercapacitors. [ABSTRACT FROM AUTHOR]

Objectives: Using food to prevent diseases has become the focus of different researchers in recent years. Tea is a natural source of caffeine, flavonoids, ascorbate, theanine, and antioxidants. The purpose of this study was to provide a review of the benefits and harms of tea for different body systems. Methods and Materials: The present review study was conducted by searching through the websites and assessing the results in the literature using a library research method. The data were collected for publications during 2000-2018. Results: Various epidemiological studies concluded that tea and its polyphenolic contents have beneficial effects on different bodily systems including the cardiovascular system, diabetes control, and different types of cancer. However, some studies argue that tea may have harmful effects on the bodily systems. Conclusions: Overall, tea is considered beneficial to human health. It can also be recommended as a healing beverage. Nevertheless, conflicting findings are reported about the risks of tea as well. Therefore, more studies are needed to further explore the benefits and possible harms of different types of tea. [ABSTRACT FROM AUTHOR]

Recently, the environmental pollutions (air, water and soil) caused by the release of large amount of toxins, through extensive industrialization, have received a great attention by the environmental scientists. Thus, there is a serious need for efficient environmental remediation approaches. Recently, nanomaterials have obtained immense interest due to their enormous prospective in the environmental remediation. Researchers have developed biocompatible and safer tools for the development of nanomaterials. This review article is demonstrating that how different biocompatible nanomaterials are synthesized and used for the ecological remediation applications. Different schemes are explained for the synthesis of nanomaterials with high biocompatibility and their application in the field of environmental remediation. The use of various functional nanomaterials for the treatment of environmental pollutions (air, water and soil) is discussed in detail. [ABSTRACT FROM AUTHOR]

An anthracene carboxyimide derivative was synthesized as a colorimetric and fluorogenic sensor to determine NO2− with a rapid response (<4 min), excellent selectivity and a low detection limit (84 nM). Paper strips containing the sensor were applied to visually determine the NO2− content in food. [ABSTRACT FROM AUTHOR]

Summary: Hydrogen becomes one of the most clean energy sources. The major issues on hydrogen are lack of practical clean and high‐temperature processes and possible practical storage of clean hydrogen. An energy intensive of clean hydrogen storage via chemical and liquid fuel production route is the current demand. This article reviewed the most recent research for hydrogen (H2) production by using several methods, such as thermochemical process, thermal decomposition, biological approaches, electrolysis, and photocatalytic method. H2 storage types, including physical and chemical approaches, were also reviewed. The produced H2 was stored as valuable chemicals and fuels via CO2 hydrogenation reaction. Reactor designs are the illustrated number of design ranging from the fixed bed to the continuous stirred tank reactor. Catalyst type, catalytic system, and the related mechanism of CO2 hydrogenation reaction to form alcohol, alkanes, and carboxylic acid were also discussed in detail. [ABSTRACT FROM AUTHOR]

Heterogenous Fenton‐like reactions are frequently proposed for treating persistent pollutants through the generation of reactive radicals. Despite great efforts to optimize catalyst activity, their broad application in practical settings has been restricted by the low efficiency of hydrogen peroxide or persulfate decomposition as well as ultrafast self‐quenching of the activated radicals. Theoretical calculations predicted that two‐dimensional (2D) metallic 1T phase MoS2 materials with exposed (001) surfaces and (100) edges should have remarkable affinity towards crucial intermediates in the peroxymonosulfate (PMS) activation process. X‐ray photoelectron spectroscopy and in situ Raman spectroscopy were used to show that the exposed metallic Mo sites accelerate the rate‐limiting step of electron transfer. A lamellar membrane made from a stack of 2D MoS2 with tunable interspacing was then designed as the catalyst. The non‐linear transport between the MoS2 nanolayers leads to high water diffusivity so that the short‐lived reactive radicals efficiently oxidize contaminants. [ABSTRACT FROM AUTHOR]

In this paper, we establish a cold chain dynamic game model including a milk manufacturer and two downstream oligopoly supermarkets under the wholesale price contract in the real world. The manufacturer is responsible for the production and cold transportation, and the two retailers sell the product. The Nash equilibrium points and the complexity of the system are discussed. The influence of the decision parameters and the stability of the system are studied by using complexity theory. We reveal the stable regions for the dynamic system. In addition, revenue sharing contract and profit sharing contract are two valuable contracts. In order to see how the two contracts would impact on the system's equilibrium solution and the profits, we establish and analyze two new dynamic models for the cold chain. By the comparison of the analyses under three contracts, we find that the manufacturer's effort of cold transportation will change under different contracts, and the profit distribution of the whole cold chain will be affected. Chaos control is also studied by the method of delay feedback control, in order to provide some management advice. [ABSTRACT FROM AUTHOR]

Tracking of necrosis avid agents is of crucial importance toward understanding their mechanisms. We explored the cellular localisation of rhein by synthesising a clickable derivative (compound 3) and labelling it in situ with an Alexa-fluor 488 click partner. Binding to exposed DNA may be an important mechanism of targeting of rhein compounds to necrotic cells. [ABSTRACT FROM AUTHOR]

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Single‐composition Ba2Y2Si4O13:Bi3+,Eu3+ (BYSO:Bi3+,Eu3+) phosphors with color‐tunable and white emission were prepared by conventional high temperature solid‐state reaction method. The structural and luminescent properties of these phosphors were thoroughly investigated through X‐ray diffraction, photoluminescence, and decay curves. BYSO:Bi3+ phosphors show two excitation peaks at 342 and 373 nm, and give two emission peaks at 414 and 503 nm, respectively, indicating that there are two sites of Bi3+ in BYSO. The energy transfer from Bi3+ to Eu3+ was investigated in detail. Varied hues from blue (chromaticity coordinate [0.219, 0.350]) to white (0.288, 0.350) and orange‐red light (0.644, 0.341) can be generated by adjusting the content of Eu3+. Pure white light emission (0.311, 0.338) can be obtained under the excitation of 355 nm in BYSO:3%Bi3+,20%Eu3+ phosphor. Besides, BYSO:Bi3+,Eu3+ phosphors exhibit distinct thermal quenching properties, whose emission intensity at 473 K is 82.6% of that at 298 K. Our results indicate that BYSO:Bi3+,Eu3+ may be applied as conversion phosphors for n‐UV‐based W‐LEDs. [ABSTRACT FROM AUTHOR]

Designing low-cost and effective electrode materials is a pressing but challenging task for fabricating electrochemical sensors. Herein, a pH-regulated electrodeposition method was proposed for the facile synthesis of CuOx/electrochemically reduced graphene oxide (ERGO) nanohybrids. Besides, the relationships between the structures of CuOx/ERGO nanohybrids and the corresponding properties were investigated. It was found that the CuOx/ERGO nanohybrid-based electrochemical sensor displayed different catalytic abilities towards nitrite sensing, following the order honeycomb-like structure ＞ peony-like structure ＞ rose flower-like structure ＞ crape myrtle flower-like structure. Honeycomb-like CuOx/ERGO nanohybrids were used to fabricate an electrochemical sensor. This sensor not only achieved accurate and sensitive detection of nitrite in a wide linear range of 0.1–100 μM with a low detection limit of 0.072 μM but could also be applied in the detection of nitrite in drinking water and meat samples with acceptable recovery and stability. The established method may have potential application value for on-site safety regulation on nitrite in the environment and food. And, research on the structure–property relationship of the electrode modified material has certain theoretical value for the development of new methods for electrocatalytic nitrite oxidation. [ABSTRACT FROM AUTHOR]

The photovoltaic effect occurs at the interface between two different types of semiconductors that are joined together to create a p–n junction, and it has been explored as a basic principle to harvest solar energy to generate electricity. The active materials are typically protected from water for stable performances, and the photovoltaic effect is observed in photovoltaic materials with appropriate energy bands and interfaces. Here we have discovered another new and general photo-to-electricity phenomenon in semiconducting materials in water. The photo-to-electricity conversion could be realized by using the identical type of semiconductor as the active material. Aligned carbon nanotube sheets were demonstrated to output high open-circuit voltages up to 0.48 V. Due to the intrinsic flexibility of the designed carbon nanotube sheets, the output voltage could be well maintained after deforming for 8000 cycles. [ABSTRACT FROM AUTHOR]

MicroRNAs are small non-coding RNA regulatory molecules that play an important role in the development and function of immune cells. MicroRNA-26a (miR-26a) exhibits anti-inflammatory immune effects on immune cells. However, the exact mechanism by which miR-26a plays an anti-inflammatory role remains unclear. Here, we report that miR-26a reduces inflammatory response via inhibition of prostaglandin E2 (PGE2) production by targeting cyclooxygenase-2 (COX-2). We found that miR-26a was downregulated in vitro and in vivo. The miR-26a mimic significantly decreased COX-2 protein levels, further inhibiting pro-inflammatory cytokine production in LPS-stimulated macrophages. We predicted that miR-26a could potentially target COX-2 in LPS-stimulated macrophages. Computational algorithms showed that the 3'-UTR of COX-2 mRNA contains a binding site for miR-26a. This putative targeting relationship between miR-26a and COX-2 was further confirmed by a dual-reporter gene assay. The anti-inflammatory effects of the miR-26a mimic were diminished by PGE2 supplementation. Importantly, miR-26a mimics protected mice from lethal endotoxic shock and attenuated pro-inflammatory cytokine production. Collectively, these results suggest that miR-26a may function as a novel feedback negative regulator of the hyperinflammatory response and as a drug target for the progression of inflammation., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Alpha-synuclein (α-syn), encoded by the SNCA gene, is a major participant in the pathophysiology of Parkinson's disease (PD). Its functions have been reported to be related to apoptosis induction, the elevation of oxidative stress, mitochondrial homeostasis, cell-cycle aberrations, and DNA-related interactions. Evidence obtained in recent studies suggests a possible link between α-syn and cancer development. Bladder cancer (BCa) is the second most common genitourinary malignancy, with the population of survivors of BCa increasing worldwide. In this study, we show that α-syn expression was significantly downregulated in BCa. In vitro and in vivo experiments showed that α-syn could significantly inhibit BCa cell proliferation by arresting the cell cycle in the S phase via upregulation of p53 expression mediated by DNA damages. Further experiments showed that overexpression of α-syn delivered by adeno-associated viruses (AAVs) exerted inhibitory effects on the growth of BCa tumors. These findings indicate that αα-syn is a functional tumor suppressor that can inhibit the proliferation of BCa cells by activating the p53/p21 signaling pathway. Our present study provides insights into the roles of α-syn in BCa and suggests that α-syn may be a novel therapeutic target for the treatment of BCa., (© 2022. The Author(s), under exclusive licence to Springer Nature America, Inc.)

The results of studies of technological conditions of formation of LEDs on the basis of an InGaN/GaN micropyramid in the core/shell geometry using a semi-transparent Ni/Au/graphene contact have been presented. The structures have been formed by the method of metalorganic vapor-phase epitaxy. The development of the tranfer conditions of large-area graphene obtained by chemical-vapor deposition has allowed the using of it as a contact for current injection. The fabricated LEDs have demonstrated electroluminescence at a wavelength of 520-540 nm. These sources of radiation are of interest for biomedical applications— in particular, for optogenetics. [ABSTRACT FROM AUTHOR]

In this work, uniform rose-like MoS2 hierarchitectures have been succefully synthesized on a large scale through a template-free hydrothermal method by the reaction of hexaammonium heptamolybdate tetrahydrate [(NH4)6Mo7O24·4H2O] and thioacetamide (CH3CSNH2). The rose-like MoS2 hierarchitectures have a diameter of 350-450 nm and are formed by the assembly of numerous nanosheets. A reasonable growth mechanism of the MoS2 hierarchitectures was proposed according to the time-dependent experiments. In addition, the as-prepared rose-like MoS2 hierarchitectures show a large specific surface area of 33.72 m2 g−1 with a dominant pore diameter of 46 nm. UV-Vis absorption spectrum indicated that the sample shows a large blue-shift compared to bulk MoS2. The photocatalytic properties were investigated and exhibit enhanced visible light photocatalytic performance with the assistence of H2O2, which can be attributed to the special structural feature with an open and porous nanostructured surface layer that significantly facilitates the diffusion and mass transportation of MB molecules and oxygen species in photochemical reaction of MB degradation. This resulting rose-like MoS2 hierarchitectures are very promising visible light photocatalysts for the degradation of dye pollutants and other applications. [ABSTRACT FROM AUTHOR]

Oolong tea (OT) is a traditional Chinese tea (Camellia sinensis) and is especially popular in south China. This review is to comprehensively summarize the miscellaneous research that has been done towards to the processing, phytochemistry, health benefit, and risk of OT. These literatures were carried out not only from different electronic databases but also from text books written in English, Japanese, and Chinese, including those traditional records tracing back to the Tang Dynasty (A.D. 618-907). The full process OT producing is depicted below in this review. The phytochemistry of OT has been comprehensively investigated. More than 100 chemical compositions have been isolated and identified. In health benefit, OT performs outstandingly in reducing obesity and controlling diabetes explained by modern pharmacological studies. (-)-Epigallocatechin-3-gallate (6) in OT prevention of cancerous cells developing. OT can also improve and reduce on heart and vascular disease, protect teeth and bone, function as anti-oxidative and antibacterial agents. This review also mentioned the risk, summarized briefly on various forms of toxicity and harmful associated with OT. In short, this review can provided a natural product library of OT, gave inspirations for further new garden systems, designed idea on quality, bioactivity-oriented screening. In addition, it is suggested more scientists and education is necessary to guarantee the stability and safety of drinking OT. [ABSTRACT FROM AUTHOR]

Formic acid and formates are often produced by hydrogenation of CO2 with hydrogen over homogeneous catalysts. The present review reports recent achievements in utilization of heterogeneous catalysts. It shows that highly dispersed supported metal catalysts are able to carry out this reaction by providing activation of hydrogen on the metal sites and activation of CO2 or bicarbonate on the support sites. Important advances have recently been achieved through utilization of catalysts using CxNy materials as supports. The high activity of these catalysts could be assigned to their ability to stabilize the active metal in a state of single-metal atoms or heterogenized metal complexes, which may demonstrate a higher activity than metal atoms on the surface of metal nanoparticles. [ABSTRACT FROM AUTHOR]

Thunbergia laurifolia (TL) Linn., a Thai medicinal herb, has been used as a herbal tea for detoxification of poisons and antipyretic purpose. Its antioxidant activity and related biological effects have also been reported. The active markers of the TL tea were caffeic acid (CA) and rosmarinic acid (RA). Although this tea has been used for decades, the information relating to its optimal infusion condition was limited. Therefore, this study was aimed to preliminary investigate the effect of infusion variables which were infusion time, water temperature and volume, on the CA and RA contents transferred into the tea solutions. To evaluate the efficiency of extraction methods, the marker contents obtained by infusion and aqueous extraction process were compared. Furthermore, the infusion variables were optimized to obtain maximum antioxidant activity by using response surface methodology (RSM). The 2,2- diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity was used as a model response. The results demonstrated that the contents of CA and RA in the tea solutions varied considerably according to the infusion conditions, which may be critical for the therapeutic efficacy of the tea. More importantly, after infusion, the major portion of active markers remained in the tea powder implying low efficiency of the infusion method. By using RSM, it was successfully found that the maximum DPPH activity was obtained when infusing the TL tea in 200 mL of boiling water for 15 min. The results of this study can help further understanding of the maximal health benefits to be attained through consumption of TL tea. [ABSTRACT FROM AUTHOR]

In this work, a colorimetric and ratiometric fluorescent probe, 2,3-bis(((E)-4-(diethylamino)-2-hydroxybenzylidene)amino)maleonitrile (DHM), was developed based on N2H4-induced bond cleavage. Two cyanide groups of DHM were applied to sense hydrazine (N2H4) for the first time, which was demonstrated using 1H NMR and HRMS spectra. The specific ‘C-CN’ bond cleavage induced by N2H4 showed an excellent fluorescence ratiometric behavior and a visible colorimetric change from purple to yellow. Meanwhile, it showed a low detection limit of 58.1 nM (1.65 ppb), which is far below the safety level (10 ppb) set by the U.S. EPA. Moreover, the probe was successfully employed for the quantitative detection toward N2H4 in real water samples. [ABSTRACT FROM AUTHOR]

This article intends to cover the latest progress and innovations in the field of graphene-based sensors for the detection of hydrogen peroxide (H2O2). The studies on the electrochemical behavior of a bioactive molecule have become one of the most rapidly developing fields. Biomedical engineering and biotechnology have an enthroned interest in fabricating more precise and accurate voltammetric/amperometric biosensors. One hastily growing area of biosensor design calls for the incorporation of carbon-based nano-materials such as two-dimensional graphene and its derivatives. Herein, a brief overview depicting the voltammetric techniques and how these techniques are useful in biosensing and sensing along with the details of surrounding important concepts such as sensitivity and limits of detection have been discussed in detail. The article discusses the graphene-based research for the effective immobilization of the enzymes such as horseradish peroxidase, hemoglobin, etc. for the accurate detection of H2O2 along with the detailed discussion on various material developed for the fabrication of non-enzymatic H2O2 sensors. The discussion ends with an outlook of future concepts that can be employed in sensor fabrication, as well as restrictions of already proposed materials and how such sensing can be improved. As such, this article can act as a roadmap to direct researchers in the direction of the next generation sensors highlighting the current advancements in the field. [ABSTRACT FROM AUTHOR]

Introduction: Phenolic compounds have been widely credited as an important part in various human ailments and plants’ disease resistances. Few studies, however, focused on the method to extract and detect the contents of phenolic compounds in the stems of Dendrobium officinale, a prized medicinal plant and functional food in China. Materials and methods: In this work, a very rapid, sensitive and reliable reverse-phase high-performance liquid chromatography (RP-HPLC) method was established for the separation and quantification of two phenolic compounds, i.e., quercetin and erianin in D. officinale stems, but also an optimized extraction process. Result and discussion: Results showed that quercetin and erianin were eluted before around 35 min, providing a time-saving separation. Furthermore, the steeper gradient rate in the range of 2.66-4.85% acetonitrile/min was the best for the elution. Meanwhile, the maceration of 30 min by the extraction solvent should be performed for removing polysaccharides that interfered the detection of phenolic components and resulted in the blockage of the chromatographic column, followed by a shorten ultrasonic-assisted extraction time of 30 min. The solid-liquid ratio was 1:100. Conclusions: This method is broadly applicable for chemical analyses of phenolic components in other Dendrobium species, for which similar problem may emerge. [ABSTRACT FROM AUTHOR]

Advertising and sales promotion are two important specific marketing communications tools. In this paper, Internet sales promotion is introduced into a differential advertising model and investigated quantitatively. The conditions for the existence and stability of periodic solutions are obtained. Flip bifurcation of periodic solution is investigated analytically. The results show that the sales promotion parameter can modify the stability of the differential advertising model and lead to chaos through flip bifurcation, the sales level will eventually be no less than a given value by adjusting the value of the sales promotion parameter, and the optimal sales promotion strategy can lead to maximum profit. Numerical results for periodic solutions, bifurcation diagrams, and the effects of sales promotion strategies, which are illustrated with an example, are in good agreement with the theoretical analysis. These results have certain significant theoretical and practical value in related markets. [ABSTRACT FROM AUTHOR]

Abstract: CO2 methanation catalysts were prepared by co-sputtering with Ru and metal oxides such as TiO2 and ZrO2 using the polygonal barrel-sputtering method. The co-sputtering technique not only resulted in the decrease in the reaction temperature but also maintained the deposition of smaller Ru particles during the reaction at higher temperature.Graphical Abstract: [ABSTRACT FROM AUTHOR]

The search for high capacity, low-cost electrode materials for lithium-ion batteries is a significant challenge in energy research. Among the numerous potential candidates, layered compounds such as MoS2 (Molybdenum Disulfide) have attracted increasing attention. A facile hydrothermal reduction process using hexadecyltrimethy ammonium bromide (CTAB) as surfactant was developed for the synthesis of lithium-ion battery anode material MoS2 nanoflowers. The impact of CTAB on morphology and electrochemical performance of MoS2 has been investigated. With the increase of CTAB content, MoS2 ultrathin nanosheets with high specific surface area and more active sites have been successfully synthesized. Electrochemical measurements demonstrated that MoS2 nanoflowers synthesized with 1% content of CTAB have better electrochemical performance than others as anode materials for Li-ion batteries, which yield a high discharge capacity of 1245 mAh g−1 at a current density of 50 mA g−1 and a stable capacity retention of 740 mAh g−1 until 100 electrochemical cycles. [ABSTRACT FROM AUTHOR]

High performance microwave absorber consisting of Fe@Ni nanoparticles (NPs) modified reduced graphene oxide (RGO) and epoxy resin was successfully prepared. Fe@Ni NPs obtained via electroless plating method could be simply anchored on the surface of RGO sheets because of its high surface area, as well as residual organic groups of RGO. The crystal/micro-structure and magnetic properties of as-synthesized samples were subsequently analyzed by XRD, SEM, TEM, XPS and VSM, while electromagnetic properties were tested by vector network analyzer. The synergistic effect between graphene and Fe@Ni NPs generated suitable impedance match and strong microwave attenuation ability which lead to excellent microwave absorption property. The optimal reflection loss (RL) calculated from measured electromagnetic parameters can reach up to − 22.7 dB at 14.9 GHz with a layer thickness of 2 mm. Moreover, RL values < − 10 dB is found to be 5.5 GHz within 12.5–18 GHz, almost covering the entire Ku band. It’s convincing that the as-synthesized composites are potential candidates for high-performance lightweight microwave absorbers. [ABSTRACT FROM AUTHOR]

Cisplatin (CDDP) isan anti-cancerDNA alkylating chemotherapeutic agent act against a variety of tumors.The present study aimed to evaluate the possible protective effects of green tea on the physiological parameters in mice chronically treated with CDDP. Four groups of mice were examined: a control mice saline PBS solution (group I), mice treated with CDDP (group II), mice treated with CDDP and green tea (group III) and normal mice treated with green tea (group IV). All animals were treated for successively five days and killed one week after the last treatment. The results recorded that CDDP treatment significantly decreasedthe levels of white blood cells (WBCs), red blood cell distribution width (RDW) and lymphocytes count. Also, CDDP increased the hepatocytes oxidative stress which characterized by increasing prooxidants xanthine oxidase (XO), thiobarbituric acid-reactive substances (TBARS) and decreasing of antioxidants glutathione peroxidase (GPx). As a result, hepatocytes injury took place that characterized with serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) andalkaline phosphatase (ALP) activities. The treatment of mice with green tea to CDDP group (group III) or mice treated with gr een tea alone group (group IV) successfully normalized the physiological parameters in form returning WBCs, RDW and lymphocytes counts to normal levels and decreased the hepatocytes oxidative stress which characterized by decreasing Prooxidants (OX, TBARS) and increasing of antioxidants GPx reflected by significant decrease in the serum activities of AST, ALTand(ALP) activities. [ABSTRACT FROM AUTHOR]

In the past decades, numerous efforts have been devoted to improving the catalytic activity of nanocomposites by either exposing more active sites or regulating the interaction between the support and nanoparticles while keeping the structure of the active sites unchanged. Here, we report the fabrication of a Co 3 O 4 -CeO 2 nanocomposite via overturning the loading direction, i.e., loading an inert CeO 2 support onto active Co 3 O 4 nanoparticles. The resultant catalyst exhibits unexpectedly higher activity and stability in peroxymonosulfate-based Fenton-like reactions than its analog prepared by the traditional impregnation method. Abundant oxygen vacancies (O v with a Co⋅⋅⋅O v ⋅⋅⋅Ce structure instead of Co⋅⋅⋅O v ) are generated as new active sites to facilitate the cleavage of the peroxide bond to produce SO 4 .- and accelerate the rate-limiting step, i.e., the desorption of SO 4 .- , affording improved activity. This strategy is a new direction for boosting the catalytic activity of nanocomposite catalysts in various scenarios, including environmental remediation and energy applications., (© 2022 Wiley-VCH GmbH.)