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• The kinetics of m -phenylenediamine monoacylation was studied in a microreactor. • The possible reaction mechanism was postulated from the kinetics study. • The accuracy of the kinetic model was proved by validation experiments. • The effect of each parameter on selectivity was studied by the kinetic model. Monoacylated symmetrical diamines are building blocks or intermediates of several well-established drugs. However, for the symmetrical diamines, the two amine groups located in a similar chemical environment make the selective monoacylation rather difficult and no kinetics study has ever been reported before. To comprehend this kind of reaction more deeply, a continuous flow microfluidic system was developed to evaluate the reaction kinetics of m -phenylenediamine and benzoic anhydride. At first, the reaction order of each reactant, pre-exponential factors and activation energies were determined in turn. The possible reaction mechanism was postulated from the reaction order. Then, a series of validation experiments were designed to show the accuracy and the applied range (concentration and temperature) of the kinetic model. Next, to obtain a controlled selectivity, the effects of initial concentration, reaction temperature and molar ratio on the selectivity were investigated through the model simulation. In the end, under the conditions optimized by the kinetic model, 96.9% selectivity and 92.5% yield were obtained in the microreactor. [ABSTRACT FROM AUTHOR]

• An HPLC method was developed to evaluate the intrinsic stability of L-α-glycerylphosphorylcholine (L-α-GPC). • The HPLC method was validated with respect to precision, accuracy and robustness. • L-α-GPC was stable under photolysis, thermal, oxidative and acidic conditions. • L-α-GPC degrades under alkaline conditions due to the specific breakage of characteristic phosphate ester bond. • A preliminary kinetics study for the degradation was conducted with the rate constant and half-life calculated. L-α-Glycerylphosphorylcholine (L-α-GPC) is effective to control the symptoms of cognitive decline for the patients of Alzheimer's disease. In this study, an HPLC method coupled with a refractive index detector was developed to evaluate the intrinsic stability of L-α-GPC. The separation of L-α-GPC and its major potential degradation products was achieved on a normal-phase silica gel column (4.6 mm × 250 mm) with the mobile phase consisting of methanol–20 mM ammonium formate aqueous solution (pH 3.2) (65:35, v/v) in isocratic mode. The HPLC method was validated satisfactorily with respect to precision, accuracy and robustness. It is found that L-α-GPC is stable under the photolytic, thermal, oxidative and acidic conditions, while relatively sensitive to alkaline condition due to the specific breakage of phosphate ester bond in the moiety of L-α-GPC. A preliminary kinetics study for the alkaline degradation was conducted with the corresponding kinetics parameters obtained. It can be concluded that the developed HPLC method is capable of distinguishing the stability difference between the two phosphate ester bonds characterized on the L-α-GPC chemical structure. [ABSTRACT FROM AUTHOR]

• Renewable non-edible seeds were used for pyrolysis. • Seven models were used to determine kinetic parameters. • Kinetic reaction data showed good agreement with experimental data. • VZ and DAEM methods produce minimal error compared with others. The present study addressed the kinetics characteristics and pyrolysis behaviour of waste biomass Azadirachta indica (NM) and Phyllanthus emblica kernel (AM) in a thermogravimetric analyzer. Six model-free techniques such as Kissinger-Akahira-Sunose, Distributed Activation Energy Model, Friedman, Coats-Redfern, Ozawa-Flynn-Wall, Vyazovkin and Criado method were employed to evaluate the kinetic parameters at five varying heating rates (10–50 °C min−1). The physicochemical inspection directed that both the biomass had excellent prospects to produce energy and finest chemicals. FTIR study pointed strong evidence of moisture, protein, acid, and aromatics. The average apparent activation energy was found to be 176.66, 193.67, 196.06, 177.32 and 204.23 kJ mol−1 for NM and 184.77, 195.10, 189.95, 186.46, 184.57 kJ mol−1 for AM for KAS, OFW, FM, DAEM and VZ respectively. Further, master plot and thermodynamic study of AM and NM revealed that pyrolysis went through various reaction mechanisms at the time of pyrolysis. [ABSTRACT FROM AUTHOR]

• Different morphologies of MgO samples were synthesized. • Ternary nitrates were used to promote the CO 2 adsorption performance of MgO. • The kinetic of MgO derived adsorbents for CO 2 adsorption were analyzed. • The adsorption mechanisms of MgO derived adsorbents were discussed. In this paper, the magnesium chloride hexahydrate (MgCl 2 ·6H 2 O), magnesium nitrate hexahydrate (Mg(NO 3) 2 ·6H 2 O) and magnesium hydroxide (Mg(OH) 2) were used as precursors to synthesize different morphologies of MgO by hydrothermal method and precipitation method. Ternary nitrates [TNO 3 ] were invited to promote the CO 2 capture performance of the synthesized MgO samples. It demonstrated that different precursor and morphology may influence the specific surface area of the MgO, thus influence the optimized loading amount of TNO 3. The MgO sample fabricated with Mg(NO 3) 2 ·6H 2 O as precursor and potassium carbonate (K 2 CO 3) as precipitator showed the rod like morphology with the largest specific surface area, which CO 2 capture capacity can reach 10.48 mmol g−1 in 30 min and get the maximum value of 13.45 mmol g−1 in 240 min in pure CO 2 at 300 °C with loading of 20 mol% TNO 3. In addition, the Pseudo-first order (PFO) model, Pseudo-second order (PSO) model, Boyd kinetic (BK) model, and Intra-particle diffusion (IPD) model were proposed to investigate the limiting factors and adsorption behavior of MgO derived CO 2 adsorbent. At last, the adsorption mechanisms of MgO derived CO 2 adsorbent with or without TNO 3 loading were discussed. [ABSTRACT FROM AUTHOR]

• A barrier discharge of the electric field was helpful to overcome mass transfer limit. • This study was enhancing the molecular collision by accelerating the reaction time. • Confirmed the reduction of surface tension between methanol and soybean oil. • The electric field offered higher yield and reduced the residence/separation time. • Over 90 % of biodiesel yield was achieved within 3 min. under the electric field. The mass transfer limitation of conventional transesterification reaction is the reason for reaction time extension and separation prolongation. In the present work, an electric field was used to overcome the mass transfer limit through barrier discharge. The ring electrode attached to a glass cylinder and the rod electrode inside the glass cylinder was applied to reduce surface tension between methanol and soybean oil, to speed up the reaction process. The 220 V AC was provided to the variable voltage transformer to create a high voltage electric field and accelerate the transesterification reaction. The results show that the optimal conditions for the transesterification process were: 1% catalyst, 6:1 M ratio of methanol/oil, agitation speed of 600 rpm, the reaction time of 30 min at different reaction temperatures (25 °C–60 °C). The maximum yield obtained after purification was 95.72 %. In addition, the kinetic study of the transesterification reaction was adequately explored in terms of a -pseudo-first-order reaction, with an activation energy of 14.35 kJ ⋅ mol−1 and a frequency factor of 0.38 s−1. The electric field turns out to enhance the transesterification process with faster reaction time efficiently, which reduces energy consumption. [ABSTRACT FROM AUTHOR]

Fourteen triterpene acids, viz., three tirucallane-type (1–3), eight ursane-type (4–11), two oleanane-type (12, 13) and one lupane type (21), along with boswellic aldehyde (14), α-amyrine (15), epi-amyrine (16), straight chain acid (17), sesquiterpene (19) and two cembrane-type diterpenes (18, 20) were isolated, first time, from the methanol extract of Boswellia elongata resin. Compound (1) was isolated for first time as a natural product, while the remaining compounds (2‒21) were reported for first time from B. elongata. The structures of all compounds were confirmed by advanced spectroscopic techniques including mass spectrometry and also by comparison with the reported literature. Eight compounds (1–5, 11, 19 and 20) were further screened for in vitro α-glucosidase inhibitory activity. Compounds 3–5 and 11 showed significant activity against α-glucosidase with IC50 values ranging from 9.9–56.8 μM. Compound 4 (IC50 = 9.9 ± 0.48 μM) demonstrated higher inhibition followed by 11 (IC50 = 14.9 ± 1.31 μM), 5 (IC50 = 20.9 ± 0.05 μM) and 3 (IC50 = 56.8 ± 1.30 μM), indicating that carboxylic acid play a key role in α-glucosidase inhibition. Kinetics studies on the active compounds 3–5 and 11 were carried out to investigate their mechanism (mode of inhibition and dissociation constants Ki). All compounds were found to be non-competitive inhibitors with Ki values in the range of 7.05 ± 0.17–51.15 ± 0.25 µM. Moreover, in silico docking was performed to search the allosteric hotspot for ligand binding which is targeted by our active compounds investigates the binding mode of active compounds and it was identified that compounds preferentially bind in the allosteric binding sites of α-glucosidase. The results obtained from docking study suggested that the carboxylic group is responsible for their biologic activities. Furthermore, the α-glucosidase inhibitory potential of the active compounds is reported here for the first time. [ABSTRACT FROM AUTHOR]

The development of ruthenium-based complexes for cancer treatment requires a variety of pharmacological studies, one of them being a drug's binding kinetics to serum proteins. In this work, speciation analysis was used to study kinetics of ruthenium-based drug candidates with human serum proteins. Two ruthenium (Ru) complexes, namely [(η6-p-cymene)Ru(1-hydroxypyridine-2(1H)-thionato)Cl] (1) and [(η6-p-cymene)Ru(1-hydroxypyridine-2(1H)-thionato)pta]PF6 (2) (where pta = 1,3,5-triaza-7-phosphaadamantane), were selected. Before a kinetics study, their stability in relevant media was confirmed by nuclear magnetic resonance (NMR). Conjoint liquid chromatography (CLC) monolithic column, assembling convective interaction media (CIM) protein G and diethylamino (DEAE) disks, was used for separation of unbound Ru species from those bound to human serum transferrin (Tf), albumin (HSA) and immunoglobulins G (IgG). Eluted proteins were monitored by UV spectrometry (278 nm), while Ru species were quantified by post-column isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS). Binding kinetics of chlorido (1) and pta complex (2) to serum proteins was followed from 5 min up to 48 h after incubation with human serum. Both Ru complexes interacted mainly with HSA. Complex (1) exhibited faster and more extensive interaction with HSA than complex (2). The equilibrium concentration for complex (1) was obtained 6 h after incubation, when about 70% of compound was bound to HSA, 5% was associated with IgG, whereas 25% remained unbound. In contrast, the rate of interaction of complex (2) with HSA was much slower and less extensive and the equilibrium concentration was obtained 24 h after incubation, when about 50% of complex (2) was bound to HSA and 50% remained unbound. [ABSTRACT FROM AUTHOR]

The hyperpolarization-activated cyclic nucleotide-gated 4 (HCN4) channel underlies the pacemaker currents, called "If," in sinoatrial nodes (SANs), which regulate heart rhythm. Some HCN4 blockers such as ivabradine have been extensively studied for treating various heart diseases. Studies have shown that these blockers have diverse state dependencies and binding sites, suggesting the existence of potential chemical and functional diversity among HCN4 blockers. Here we report approaches for the identification of novel HCN4 blockers through a random screening campaign among 16,000 small-molecule compounds using an automated patch-clamp system. These molecules exhibited various blockade profiles, and their blocking kinetics and associating amino acids were determined by electrophysiological studies and site-directed mutagenesis analysis, respectively. The profiles of these blockers were distinct from those of the previously reported HCN channel blockers ivabradine and ZD7288. Notably, the mutagenesis analysis showed that blockers with potencies that were increased when the channel was open involved a C478 residue, located at the pore cavity region near the cellular surface of the plasma membrane, while those with potencies that were decreased when the channel was open involved residues Y506 and I510, located at the intracellular region of the pore gate. Thus, this study reported for the first time the discovery of novel HCN4 blockers by screening, and their profiling analysis using an automated patch-clamp system provided chemical tools that will be useful to obtain unique molecular insights into the drug-binding modes of HCN4 and may contribute to the expansion of therapeutic options in the future.

2-(2H-Benzotriazol-2-yl)-4,6-di-tert-pentylphenol (UV 328; CAS: 25973-55-1) is an ultraviolet light (UV) absorber which belongs to the class of hydroxy phenol benzotriazoles. Therefore, UV 328 is added to plastics and other polymers due to its photostability to prevent discoloration and prolong product stability which may result in an exposure of consumers. However, information about the toxic effects on humans and the human metabolism are still lacking. In the present study, human metabolism pathways of UV 328 and its elimination kinetics were explored. For that purpose, three healthy volunteers were orally exposed to a single dose of 0.3 mg UV 328/kg bodyweight. UV 328 and its metabolites were investigated in blood and urine samples collected until 48 and 72 h after exposure, respectively. Thereby, previously published analytical procedures were applied for the sample analysis using dispersive liquid-liquid microextraction and subsequent measurement via gas chromatography coupled to tandem mass spectrometry with advanced electron ionization. UV 328 was found to be oxidized at its alkyl side chains leading to the formation of hydroxy and/or oxo function with maximum blood concentrations at 8-10 h after exposure for UV 328-6/3-OH, UV 328-4/3-OH and UV 328-4/3-CO. In contrast, a plateau for UV 328-4/3-CO-6/3-OH levels was reached around 10 h post-dosage. The highest blood levels were found for native UV 328 at 8 h after ingestion. Furthermore, biphasic elimination kinetics in blood were revealed for almost all detected metabolites. UV 328 and its metabolites did not occur in blood as conjugates. The renal elimination kinetics were very similar with the kinetics in blood. However, the prominence of the metabolites in urine was somewhat different compared to blood. In contrast, mostly conjugated metabolites occurred for renal elimination. In urine, UV 328-4/3-CO-6/3-OH was found to be the most dominant urinary biomarker followed by UV 328-6/3-OH and UV 328-4/3-OH. In total, approximately 0.1% of the orally administered dose was recovered in urine within 72 h. Although high levels of UV 328 in blood proved good resorption and high systemic availability of the substance in the human body, the urine results revealed a rather low quantitative metabolism and urinary excretion rate. Consequently, biliary excretion as part of the enterohepatic cycle and elimination via feces are assumed to be the preferred pathways instead of renal elimination., (© 2021. The Author(s).)

Aniline is a toxic chemical, and in many industries it is degraded by Fenton processes. In this study, an Fe(II)-nano-Fe 3 O 4 @PAC heterogeneous Fenton catalyst (MFC) was prepared with a coprecipitation and impregnation method, which is simple, efficient and cost effective. The results of the magnetic performance tests showed that the MFC has typical ferromagnetism properties. Nano-Fe 3 O 4 was found both on the surface and inside the pores of the powdered activated carbon (PAC). MFC was found to be an efficient catalyst in the Fenton-like process for aniline degradation. The optimal conditions were obtained by the orthogonal experimental method. The results showed that under the optimal conditions (pH = 3.00, temperature = 20°C, concentration of MFC = 1.0 g/L, concentration of H 2 O 2  = 0.27 g/L), the 5 mg/L aniline solution degradation ratio reached 91.2% and the mineralization ratio reached 75.77% in 30 min. In addition, kinetics studies indicated that the aniline degradation process follows a pseudo-first-order kinetics model. No refractory intermediate such as azobenzene, was found during the reaction. The pH value is an important factor in aniline solution degradation. This result indicates that in addition to the surface catalytic reaction, the Fenton reaction also occurs in solution. Fe 2+ /Fe 3+ on the MFC surface and Fe 2+ /Fe 3+ in solution both affect aniline degradation. This catalyst has the advantage of being easily magnetically separated from the aqueous phase. It has useful application prospects in solving organic industrial wastewater pollutions in developing countries because of its cost-effectiveness.

Combustion behaviors of large size coal pellets were studied in a novel room temperature chamber type concentrating photothermal apparatus. 4 heating rates of 4.0 °C/s, 15.1 °C/s, 52.4 °C/s and 69.4 °C/s were realized by adjusting the voltage-up rates of the heating lamps. The temperature, image, gas emission, and mass loss were synchronously detected and the reliabilities of data were strictly verified. Coal pellets presented "heterogeneous" ignition mechanism at slow (4.0 °C/s) heating rate, "joint homo-heterogeneous" at moderate (15.1 °C/s) heating rate, and "homogeneous" at sub-fast (52.4 °C/s) and fast (69.4 °C/s) heating rates. High concentrations of CO and CH 4 were evident at all heating rates. The increase of heating rate accelerated all gas generation rates and leaded to the gas yield reduction of CO but rising of CO 2. Kinetics studies of the reactions around the maximum mass loss rate were carried out ultimately. 1-dimensional diffusion mechanism model (D1) showed best correlation coefficients with the reactions at slow, moderate and sub-fast heating rates and the apparent activation energies slightly decreased from 84.45 and 66.18 to 62.28 kJ/mol. The fitting curve of reactions at fast heating rate was two-stage-style and correlated best to the 3-dimensional diffusion mechanism model based on Jander equation (D3) with activation energies of 33.74 and 11.54 kJ/mol. • A concentrating photothermal experimental platform for large size pellet combustion with wide heating rates was developed. • Ignition mechanism was heterogeneous at 4.0℃/s, joint homo-heterogeneous at 15.1℃/s, homogeneous at 52.4 and 69.4℃/s. • High concentrations of CO and CH 4 were detected under all the 4 heating rates. • Reactions in the maximum mass loss rate interval at fast heating rate belong to D3 model while the others belong to D1. [ABSTRACT FROM AUTHOR]

• Quantitative analytical modeling for radical contribution determination was established. • The PS/ZVC/US system was found to be most effective for BPAF degradation. • Oxidation products and degradation pathways of BPAF in PS/ZVC/US system were identified. • The reaction mechanism in PS/ZVC/US system was examined. Ultrasound (US) was introduced into a persulfate (PS)/zero-valent copper (ZVC) system for the degradation of bisphenol AF (BPAF). In this system, ZVC worked as a catalyst to activate PS. Compared with the PS/ZVC process, the degradation rate of BPAF in the PS/ZVC/US system raised significantly from 59.8% to 97.0% due to a synergistic interaction between sonolysis and a heterogeneous reaction. When ultrasound was 120 W at 20 kHz and initial BPAF concentration was 20 μmol/L, the BPAF could be completely removed after a 60-min reaction with 0.5 g/L ZVC, 1 mM PS. According to kinetics research, the decomposition of BPAF in a PS/ZVC/US system could be separated into two stages with a demarcation point after about 20 min of reaction via pseudo-first-order rate constants (k obs). A Quantitative analytical modeling for the study of main radicals was established, and the result indicated SO 4 ∙ - was the predominant radical in acidic conditions and both ·OH and SO 4 ∙ - were the predominant radicals in relative basic conditions. Moreover, the effects of initial persulfate dosage, initial BPAF concentration, and coexisting inorganic anions on BPAF degradation were evaluated. A high-accuracy mass spectrometer was used to study the oxidation process and potential activities were deduced. Finally, the possible reaction mechanisms in the PS/ZVC/US system is proposed that the surface heterogeneous catalysis was the key step to activate PS. This work will promote the understanding of the utilization of ZVC in advanced oxidation and also the key role of Cu + in activating PS. [ABSTRACT FROM AUTHOR]

• Bismuth silicate as novel catalysts for biodiesel production via esterification. • Bi 4 Si 3 O 12 and Bi 2 SiO 5 catalysts prepared by ultrasonic-assisted hydrothermal method. • Catalyst acidity increase by increasing sonication time to 30 min then decreased. • Catalyst sonicated for 30 min (BS 30) exhibits the highest oleic acid conversion. • The most active catalyst (BS 30) exhibits good reusability till five runs. To date, there are no research in the literature on the esterification reaction for biodiesel production using bismuth silicate as catalyst. With the assistance of ultrasonication at different times, the bismuth silicate (BS) catalysts were successfully prepared by hydrothermal method and applied in oleic acid esterification with methanol for biodiesel production. The prepared catalysts were characterized by XRD, HR-TEM, BET, NH 3 -TPD and UV-vis/DR to reveal their physicochemical and optical properties. Further, the biodiesel sample was characterized by FT-IR analysis. The results of XRD and HR-TEM–EDS confirmed the preparation of Bi 4 Si 3 O 12 and Bi 2 SiO 5 phases by hydrothermal method at different ultrasonic irradiation times. Interestingly, the surface area, pore volume, total acidity and band gap energies of the prepared catalysts increase with increasing the ultrasonic irradiation time from 10 min to a maximum value at 30 min then decreased. It was observed that the catalyst sonicated for 30 min (BS 30) (Bi 2 SiO 5) exhibited the highest esterification conversion efficiency of 90% at optimized reaction conditions of 80 °C, molar ratio of methanol to oleic acid of 120, 0.3 g of catalyst and 2 h reaction time. The reusability of BS 30 catalyst was estimated by utilizing it for five runs with catalytic efficiency of 80%. [ABSTRACT FROM AUTHOR]

Arsenic contamination in industrial and mining effluents has always been a serious concern. Recently, nano-sized iron particles have been proven effective in sorptive removal of arsenic, because of their unique surface characteristics. In this study, green synthesis of iron nanoparticles was performed using a mixed extract of two plant species, namely Prangos ferulacea and Teucrium polium, for the specific purpose of arsenic (III) removal from the aqueous environment. Results of UV-visible spectrometry, X-ray powder diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR) analyses confirmed the formation of iron nanoparticles from Prangos ferulacea (Pf) and Teucrium polium (Tp) extracts. The synthesized Fe nanoparticles morphology was studied via microscopy imaging. The particle size was 42 nm, as assessed by dynamic light scattering (DLS) analysis. Adsorption experiments were also designed and performed, which indicated 93.8% arsenic removal from the aqueous solution at 200 rpm agitation rate, 20 min agitation time, pH 6, initial concentration of 0.1 g/L, and adsorbent dosage of 2 g/L. Adsorption isotherm models were investigated, and the maximum uptake capacity was determined to be about 61.7 mg/g. The kinetic data were best represented by the pseudo-second kinetic model (R2 = 0.99). The negative value of Gibbs free energy, the enthalpy (−7.20 kJ/mol), and the entropy (−57 J/mol·K) revealed the spontaneous and exothermic nature of the adsorption process. Moreover, the small quantity of the activation energy confirmed the physical mechanism of arsenic adsorption onto iron nanoparticles and that the process is not temperature sensitive. [ABSTRACT FROM AUTHOR]

Extensive and inappropriate use of steroids in drugs and pharmaceutical products and improper release of steroids into the immediate environment has found to affect soil and water resulting in imbalance of ecosystem. The steroids reach environment due to inaccurate disposal of expired drugs as well as manufacturing disposal from pharmaceutical industries and are urgently required to be removed from the environment. The present study deals with elimination of 17 β‐estradiol (E2) using Trichoderma citrinoviride AJAC3. The fungal isolate could tolerate E2 and degrade 99.6% of the contaminant at concentration of 200 mg L−1. Trichoderma citrinoviride AJAC3 secreted extracellular ligninolytic enzymes which played significant role in degradation of E2. High Performance Liquid Chromatography (HPLC) was used to determine the biodegradation pattern of E2 and confirmed by Gas Chromatography Mass Spectroscopy (GC–MS), Scanning Electron Microscopy (SEM), and Fourier Transform Infrared Spectroscopy (FTIR) analysis. Kinetics study revealed that the degradation pathway followed first‐order kinetic model. The results affirmed that the isolate was able to biodegrade E2 efficiently. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13142, 2019 [ABSTRACT FROM AUTHOR]

Recycled paper mill effluent (RPME) consists of various organic and inorganic compounds. In this study, modified anaerobic hybrid baffled (MAHB) bioreactor has been successfully used to anaerobically digest RPME. The anaerobic digestion was investigated in relation to methane production rate, lignin removal, and chemical oxygen demand (COD) removal, with respect to organic loading rate (OLR) and hydraulic retention time (HRT). The analysis using kinetic study was carried out under mesophilic conditions (37 ± 2 °C) and influent COD concentrations (1000-4000 mg L -1 ), to prove its practicability towards RPME treatment. First-order kinetic model was used to clarify the behavior of RPME anaerobic digestion under different OLRs (0.14-4.00 g COD L -1  d -1 ) and HRT (1-7 d). The result shows that the highest COD removal efficiency and methane production rate were recorded to be 98.07% and 2.2223 L CH 4  d -1 , respectively. This result was further validated by evaluating the biokinetic coefficients (reaction rate constant ( k ) and maximum biogas production ( y m )), which gave values of k  = 0.57 d -1 and y m = 0.331 L d -1 . This kinetic data concludes that MAHB presented satisfactory performance towards COD removal with relatively high methane production, which can be further utilized as on-site energy supply.

In recent years, germanium nanoparticles (Ge NPs) have attracted considerable research attention because of its excellent electrical and optical properties. However, it is mainly applied in the field of solar cells, photodetectors and photothermal therapy. Actually, Ge NPs have the advantages of low toxicity and excellent biocompatibility, which means that they have great potential in biosensing applications. However, there are few related reports. In this paper, we discovered that Ge NPs have the intrinsic peroxidase-like catalytic activity and can significantly accelerate the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) by H 2 O 2 for the first time. Compared with natural enzyme (horseradish peroxidase, HRP), Ge NPs maintain higher catalytic stability after treatment at different pH, temperature and ionic strength. Furthermore, a Ge NPs-based colorimetric platform was established for the first time to detect biomolecules with favourable sensitivity and selectivity, such as uric acid, glucose and choline. This work finds the new property of Ge NPs and extends its application in biosensing., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Compared to traditional anaerobic digestion (AD), high solid anaerobic digestion (HSAD) had the advantages of small digester, low heating energy and less digestate. However, the methane production was poor. In our previous study, thermal treatment (70 ± 1 °C, 3 days) without any dilution could satisfactorily enhance the methane production rate of HSAD by up to 39.5%. However, effects of solid content on HSAD after thermal treatment were not yet studied. In this study, HSAD was conducted at 11.7-17.6% solid content, and the control experiment was conducted at low solid content (4.4% solid content). Results showed that HSAD's methane production rate was the highest at 11.7% solid content (158 mL CH 4 /g VS), and could reach up to 89.2% of that at 4.4% solid content. The utilization of organics was revealed by kinetics analysis that the readily biodegradable organics could be utilized at increasing solid content with decreasing hydrolysis rate. Furthermore, it was notable that methylotrophic methanogens predominated in HSAD with the abundance of 82.6%. This was quite unique from the general belief that AD system was usually dominated by acetoclastic or hydrogenotrophic methanogenic pathways. In this study, the microbial community structure of HSAD after thermal treatment was firstly studied, its unique specific methanogenic pathways was firstly revealed., (Copyright © 2019. Published by Elsevier Ltd.)

A novel series of aniline-containing hydroxamic acids were designed, synthesized and evaluated as anti-virulence agents for the treatment of gastritis and gastric ulcer caused by Helicobacter pylori. In vitro enzyme-based screen together with in vivo assays and structure-activity relationship (SAR) studies led to the discovery of three potent urease inhibitors 3-(3,5-dichlorophenylamino)N-hydroxypropanamide (3a), 3-(2-chlorophenylamino)N-hydroxypropanamide (3d) and 3-(2,4-dichlorophenylamino)N-hydroxypropanamide (3n). Compounds 3a, 3d and 3n showed excellent urease inhibition with IC 50 values 0.043 ± 0.005, 0.055 ± 0.008 and 0.018 ± 0.002 μM, and significantly depressed gastritis developing at the dose of 32 mg/kg b. i.d with eradication rates of H. pylori reaching 92.3, 84.6 and 100%, respectively. Preliminary safety studies (acute toxicity in mice) disclosed that 3a, 3d and 3n was well-tolerated in KM mice with LD 50 s of 2982.8, 3349.4 and 3126.9 mg/kg, respectively. Collectively, the data obtained in this study indicate that 3a, 3d and 3n, in particular 3n, could considered as promising candidates for the potential treatment of H. pylori caused gastritis and gastric ulcer, and hence merit further studies., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Stability-indicating high-performance liquid chromatography (HPLC) and spectrofluorimetric methods were developed for determination of empagliflozin (EGF). EGF was subjected to oxidation, wet heat, photo-degradation, acid hydrolysis and alkali hydrolysis. The alkaline degradation pathway was subjected to a kinetics study as the major product obtained after stress conditions. Arrhenius plots were constructed and the activation energies of the degradation process were calculated. HPLC was used for the kinetic study as it enabled simultaneous determination of EGF and the degradation product while the spectrofluorimetric assay was applied to content uniformity testing due to its higher sensitivity and lower limit of detection (LOD). Isocratic chromatographic elution was attained for HPLC on a Intersil® C 18 column (150 mm × 4 mm, 5 μm), using a mobile phase of acetonitrile-potassium dihydrogen phosphate buffer pH 4, (50:50, v/v) at a flow rate of 1 ml/min with ultraviolet (UV) detection at 225 nm. The relative fluorescence intensity was recorded by spectrofluorimeter applying synchronous mode using ∆λ = 70 nm at 297.6 nm. Linearity ranges were found to be 5-50 μg/ml and 50-1000 ng/ml for HPLC and spectrofluorimetric methods, respectively., (Copyright © 2018 John Wiley & Sons, Ltd.)

The process characteristics of microwave assisted hydrothermal carbonization of cellulose was investigated and a first order kinetics model based on carbon concentration was developed. Chemical properties analysis showed that comparing to conventional hydrothermal carbonization, hydrochar with comparable energy properties can be obtained with 5-10 times decrease in reaction time with assistance of microwave heating. Results from kinetics study was in great agreement with experimental analysis, that they both illustrated the predominant mechanism of the reaction depend on variations in the reaction rates of two co-existent pathways. Particularly, the pyrolysis-like intramolecular dehydration reaction was proved to be the predominant mechanism for hydrochar generation under high temperatures. Finally, the enhancement effects of microwave heating were reflected under both soluble and solid pathways in this research, suggesting microwave-assisted hydrothermal carbonization as a more attracting method for carbon-enriched hydrochar recovery., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The wood charcoal treated by 1N HN03 (WCT) was used to remove toxic chlorinated pesticide lindane (gamma-HCH) residue from water by the sorption process. Using a simple first order reversible kinetics constants and half time equations, the film and pore diffusion coefficients were determined. Film diffusion was found to be rate limiting step in sorbing lindane by WCT. This was further authenticated by kinetics studies at different initial sorbate concentrations, different sorbent sizes, and different agitation speeds besides interruption test. A pore diffusion model was used to fit the data of kineticsin continuously nixed batch reactors (CMBR), and the tortuosity, external resistance, and surface diffusion effects on lindane sorption by WCT were noticed. The tortuosity values of 15 to 28 were obtained for WCT-lindane system. [ABSTRACT FROM AUTHOR]