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Thermal runaway is a common hazard leading to process safety-related accidents. Uncontrolled release of chemical energy poses extreme risks for batch reactors. In this study, we fabricated encapsulated phase change materials (PCMs) with silica shells as inhibitors to improve the thermal management of reactors and mitigate reaction thermal runaway. The prepared encapsulated PCMs had core-shell microstructures and spherical morphologies, with an average particle diameter of 980 nm and a silica shell thickness of 100 nm. A series of inhibition experiments were conducted with 0.5 and 1 g of encapsulated PCMs. Three stages were identified from the inhibition experiments. Kinetic parameters of esterification of propionic anhydride with 2-butanol, catalyzed by sulfuric acid, were estimated based on an autocatalytic parallel reaction model. An inhibition effect-kinetic model was proposed to simulate the inhibition process of the thermal runaway reaction. The results revealed that thermal storage and heat transfer intensification of encapsulated PCMs play a crucial role in the inhibition process. The effect of stirring rate, dispersity of encapsulated PCMs, and warning temperature of thermal runaway while optimizing the injection strategy of inhibitors was assessed. The inhibition of thermal runaway under adiabatic conditions was relatively low.

Mixed carbon materials composed of carbon nanotubes and graphene were applied as fire retardant filler in the fire resistive coating. The fire resistance, thermal stability, water resistance and mechanical properties were investigated respectively. Scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD) were used to study the morphology and composition of the carbon chars. The results indicated that the combination of graphene and carbon nanotubes could have a synergistic effect on fire protection and thermal stability. Additionally, when the weight ratio of graphene and carbon nanotubes was 3:1, the coating exhibited “Excellent” fire resistance and flame retardancy index (FRI) was over 10. SEM, EDS, XRD analysis demonstrated that the carbon content of dense carbon layer achieved 40.97% and titanium pyrophosphate was generated. The coating with higher content of graphene exhibited better water resistance, mechanical properties and adhesion level.

Objective The aim of this study was to assess the diagnostic value of several markers for tuberculosis pleural effusion (TPE) using the combined analysis of Lactate dehydrogenase (LDH), Carbohydrate antigen 125 (CA125), Cytokeratin-19 fragment (CYFRA21-1). Methods From January to December in 2018, a total of 37 patients with pleural effusion (22 cases of transudative pleural effusion, 15 cases of tuberculosis pleural effusion and 22 cases of Transudative pleural effusion who were hospitalized in our hospital were reviewed. Receiver operating characteristic (ROC) curves and logistic regression equations was used to evaluate the diagnostic efficiency of each marker. Results The levels of LDH and CYFRA21-1 of tuberculosis pleural effusions were obviously higher than those of transudative pleural effusion with statistically significant difference ( Conclusions The study showed a high diagnostic sensitivity and specificity of combined speculation of LDH, ADA and CYFRA21-1 in Tuberculosis pleural effusion.

Diffusion bonding was successfully applied to join 304 stainless steel (SS) and tungsten (W) using interlayers of Cu and Ni, and the effect of bonding temperature on microstructure and strength of 304SS/Cu/W and 304SS/Ni/W joints is investigated. The present study shows that a sound 304SS/Cu/W joint with sufficient mutual diffusion across 304SS/Cu and Cu/W interfaces is obtained at a bonding temperature of 1000 ℃, in which solid solutions occur at Cu/W interface. The 304SS/Cu/W joint bonded at 1000 ℃ shows the highest shear strength of 277.2 MPa and good ductility. The occurrence of cracks at 304SS/Cu interface with the increasing of bonding temperature results in the decrease in shear strength of 304SS/Cu/W joints under brittle fracture. The 304SS/Ni/W joints are free of crack in the bonding temperatures of 850 ℃–1000 ℃, which shows the highest shear strength of 237 MPa bonded at 950 ℃ due to occurrence of intermetallic compound Ni4W in the diffusion layer close to Ni/W interface. No obvious diffusion layer at 304SS/Ni/W is observed following bonding at 850 ℃ and 900 ℃. The micro-voids in the diffusion layer bonded at 1000 ℃ are responsible for the lower shear strength of joint than that of 950 ℃.

Cyclic adenosine monophosphate (cAMP) is an important secondary messenger that controls carbon metabolism, type IVa pili biogenesis, and virulence in Pseudomonas aeruginosa. Precise manipulation of bacterial intracellular cAMP levels may enable tunable control of twitching motility or virulence, and optogenetic tools are attractive because they afford excellent spatiotemporal resolution and are easy to operate. Here, we developed an engineered P. aeruginosa strain (termed pactm) with light-dependent intracellular cAMP levels through introducing a photoactivated adenylate cyclase gene (bPAC) into bacteria. On blue light illumination, pactm displayed a 15-fold increase in the expression of the cAMP responsive promoter and an 8-fold increase in its twitching activity. The skin lesion area of nude mouse in a subcutaneous infection model after 2-day pactm inoculation was increased 14-fold by blue light, making pactm suitable for applications in controllable bacterial host infection. In addition, we achieved directional twitching motility of pactm colonies through localized light illumination, which will facilitate the studies of contact-dependent interactions between microbial species.

The synthesis of Grignard reagents, which are formed by the reaction of magnesium and organic halides (RX), is hazardous because of the highly exothermic nature of this reaction. In this work, calorimetry and infrared (IR) spectroscopy were used to identify the exothermic mechanism and process hazards for the synthesis of n-butylmagnesium bromide Grignard reagent (n-BuMgBr) in diethyl ether (DE), tetrahydrofuran (THF), 2-methyltetrahydrofuran (2-MeTHF), cyclopentylmethyl ether (CPME), and diethylene glycol butyl ether (DGBE). The latter three solvents were chosen by the substitution principle of the “inherent safety” design concept, which aims to reduce the risk of the target reaction in a fundamental manner. An EasyMax102 calorimeter was used to characterize the exothermic behavior of the reactions using isothermal and isoperibolic experiments carried out in a semi-batch glass reactor coupled with an IR probe to monitor changes in the species and concentrations during the reaction process. An adiabatic TAC-500A calorimeter was also used to understand the adiabatic decomposition behavior of the products obtained in the isothermal experiments under the worst-case (cooling failure and thermal runaway) scenario. Meanwhile, density functional theory calculations were performed to understand the reaction pathway and associated energies based on the experimental data. Further, the risk assessment of thermal runaway was analyzed using a risk matrix and a Stoessel criticality diagram. The results indicate that the risk of the reactions when using 2-MeTHF, CPME, and DGBE are all class 1, making reactions in these solvents inherently safer than those using DE or THF, which were both class-3 risks. These findings provide further evidence that 2-MeTHF, CPME, and DGBE are safer than the typical solvents used for the industrial production of Grignard reagents.

Renin-angiotensin system (RAS) signaling has been implicated in the development of cancer. The new RAS ACE2/Ang-(1-7)/Mas axis antagonizes the classical ACE/Ang II/AT1R axis. Ang-(1-7) has pleiotropic roles in lung cancer including suppressing proliferation, angiogenesis, and metastasis. This research was designed to investigate the effect of Ang-(1-7) on tumor-associated angiogenesis in DDP-resistant lung cancer cell lines. We first established acquired DDP-resistant cell lines A549 (A549-DDP) and LLC (LLC-DDP). We next performed RT-qPCR, western blot, ELISA, tube formation, microvessel density detection, immunohistochemistry, and tumor formation assays. The results showed that the mRNA and protein levels of RAS components and vascular endothelial growth factor A (VEGFa) were lessened in the A549/LLC-DDP+Ang-(1-7) group compared with the A549/LLC-DDP group. This effect could be blocked by the MAS receptor antagonist A779. The data revealed that Ang-(1-7) could perform its antiangiogenic function by PI3K/AKT and MAPK pathways. Furthermore, the impact of Ang-(1-7) on tumor-associated angiogenesis has been confirmed in lung cancer xenograft model with acquired DDP resistance. These results provide a theoretical basis for designing therapeutic strategies for targeting Ang-(1-7) in the treatment of NSCLC.

In this study, different calorimetric and analytical techniques were used to evaluate the thermal behaviour of the preparation of 1-nitronaphthalene through the nitration of naphthalene with mixed acid. Differential scanning calorimetry and adiabatic calorimetry revealed that 1-nitronaphthalene lacks thermal decomposition characteristics. The results of reaction calorimetry, high-performance liquid chromatography, and the density function theory method were combined to analyse the reaction mechanism. An expanded Stoessel criticality diagram was developed to evaluate the process safety of the semibatch nitration reaction. The results revealed a higher degree of risk than that obtained when using the traditional Stoessel criticality diagram. Kinetics parameters of the reaction were investigated.

In this study, the mild steel corrosion inhibition performance and the corresponding mechanisms of five imidazolium-based ionic liquids (ILs) in hydrogen sulfide (H2S) and hydrochloric acid (HCl) s...

Aim Low-temperature plasma (LTP) has potential applications in cancer therapy. Herein, we explored the molecular mechanisms of proliferation inhibition induced by LTP. Methods LTP was generated by a helium atmospheric-pressure plasma jet and used to treat A549 and H1299 cells. CCK-8 and cell apoptosis assays were performed to evaluate the effects of LTP treatment on A549 and H1299 cells. The qRT-PCR was performed to measure the expression of miR-203a after treating with LTP. CCK-8, colony formation, cell apoptosis assays, and Western blotting were performed to analyse the function of miR-203a in the development of lung cancer. Dual-luciferase assay and Western blotting were used to probe the relationship between miR-203a and BIRC5, and gene silencing using si-BIRC5 was carried out to explore the effect of knocking down BIRC5 on lung cancer cells. Results We found that LTP significantly suppressed proliferation and promoted apoptosis in A549 and H1299 cells. The miR-203a expression was increased after cells were treated with LTP. The miR-203a expression was downregulated among lung cancer tissue samples, and overexpression of miR-203a suppressed cell growth and induced apoptosis in lung cancer cells. We showed that miR-203a targeted BIRC5. Moreover, silencing of BIRC5 caused proliferation inhibition and induced apoptosis in lung cancer cells. Conclusion Our study revealed that LTP inhibited proliferation and induced apoptosis in A549 and H1299 cells through the miR-203a/BIRC5 axis. These findings showed that LTP could potentially be used to treat lung cancer.

The explosion characteristics of aluminum powder in air, hydrogen and nitrogen were studied in a 20-L spherical explosion vessel. Particle agglomeration affected the actual particle size distribution in dust clouds. In air, the smaller the actual particle size, the larger was the explosion overpressure. Adding hydrogen increased system explosion risk; the smaller the theoretical particles, the more pronounced was the effect of hydrogen. However, when hydrogen was added at a concentration of ≥ 15%, the explosive properties of the mixture weakened. In a constant volume container, the two-phase explosion of flammable gas and flammable dust caused a secondary explosion. Secondary explosion occurrence was affected by fuel composition. Experimental curve analysis explained the cause of the secondary explosion and the two-phase explosion process mechanism. Nitrogen had obvious detonation suppression effects on dust explosions. The higher the nitrogen concentration, the longer was the combustion time. Nitrogen has great influence on fine particles. These experimental conclusions may aid in preventing aluminum powder explosions during industrial production and reducing the harmful consequences of dust explosions.

Quantification of the rate of direct repeat deletion (DRD) is an important aspect in the research of DNA rearrangement. The widely used tetracycline selection method usually introduces antibiotic pressure to the tested organism, which may interfere with the DRD process. Also the length of repeat arm (LRA) is limited by the length of the TetR coding sequence. On the basis of the fluorescent microscopy and high-throughput imaging processing, here we developed a two-module genetic circuit, termed TFDEC (which stands for three-color fluorescence-based deletion event counter), to quantify the DRD rate under neutral conditions. DRD events were determined from the state of a three-state fluorescent logic gate constructed through coupling of an OR gate and an AND gate. TFDEC was applied in Pseudomonas aeruginosa, and we found that the DRD rate was RecA-dependent for long repeat arms (>500 bp) and RecA-independent for short repeat arms (

In order to develop an environmentally benign flame retardant for unsaturated polyester resins (UPR), an effective intumescent flame retardant architecture based on chitosan (CH) and ammonium polyphosphate (APP) was successfully deposited on the surface of diatomite particles by Layer-by-layer (LbL) assembly. With nine bilayers of CH/APP coating, UPR/9BL@Dia composites exhibiting LOI value of 25.7% and V-0 rating. Cone calorimetry test reveals that 9BL@Dia reduces the peak heat release rate and total heat release of UPR by 40.8% and 18.1%, respectively. Due to the unique morphology of 9BL@Dia particles, UPR/9BL@Dia composites achieves greater thermal stability and higher char yields than pure UPR. Based on the investigation of the gas and condensed phase, flame retardant mechanism of nBL@Dia was proposed as that APP/CH was heated to form phosphate esters, and then combined with diatomite to form a more stable and firm carbon structure, which can improve the fire safety of UPR composites.

We attempted to prevent the thermal risk of a runaway reaction of polymerization in a batch reactor and to realize online monitoring and emergency inhibition of the thermal runaway behavior. Styrene thermal initiation of bulk polymerization was studied. A full-size model of the styrene polymerization reactor was constructed by referring to the reactor model of the Mettler Toledo automatic calorimeter, which was combined with the kinetic and thermodynamic models of styrene polymerization. The DIV thermal runaway critical criterion based on chaos divergence theory was used to judge the thermal runaway reaction. The critical point of the runaway reaction was determined and used to inhibit the thermal runaway of styrene polymerization by injecting cooling diluents at the liquid surface. The influence of injection rate ( v c = 0.5 、 0.8 、 1 m / s ), injection position (in-1、in-2、in-3), and amount of cooling diluents (no add、50 %、70 %、100 %) injected on the thermal runaway inhibition of the reaction was investigated and elucidated. The results indicated that a better inhibiting effect can be obtained by injecting the inhibitors at higher rates near the edge of the paddle blade. Moreover, appropriately increasing the injection amount of the inhibitors can achieve better inhibition of the runaway reaction.

Hu-antigen R (HuR) is involved in the carcinogenesis and progression of multiple types of cancer. However, its precise role in gastric cancer (GC) and the relevant molecular mechanism remain largely unclear. In the present study, we found that HuR expression level was higher in GC tissues and cell lines than in adjacent normal tissues and normal gastric epithelial cell lines, and this elevated expression was found to have a significant association with lymph node metastasis. Moreover, silencing HuR with RNA interference inhibited cell viability and induced cell apoptosis through the apoptosis-related regulators (Bcl-2 and Bax) in GC cells. In addition, bioinformatic analysis revealed that HuR expression was inversely correlated with miR-145 expression in GC tissue samples, and HuR was identified as a direct target of miR-145 with the dual-luciferase reporter. Enforced expression of miR-145 inhibited the HuR expression at both mRNA and protein levels and induced similar biologic effects of silencing HuR in GC cells. Additionally, we also found that restoration of HuR could eliminate the effects induced by miR-145 in GC cells. Taken together, these findings demonstrate the exact role of the miR-145-HuR axis in the progression of GC and indicate a potential target for GC therapy.

Myogenic differentiation 1 (MyoD1) is a transcription factor that promotes expression of muscle-specific genes. MyoD1 is expressed at significantly lower levels in gastric cancer (GC) tissues and cells, and it induces apoptosis in GC cells. However, functions for MyoD1 in GC cell migration and gene expression have not been documented. We show that knockdown of MyoD1 promoted migration and invasion of GC cells, whereas MyoD1 overexpression suppressed migration and invasion. We performed chromatin immunoprecipitation (ChIP)-sequencing to identify MyoD1 target genes in MKN-45 cells. The 2-kb upstream regions (Up2k) of the transcription start sites of 57 genes were probably bound by MyoD1. Six of these genes function in signaling pathways such as synthesis of glycosphingolipid biosynthesis—lacto and neolacto series. MyoD1 inhibited transcription of fucosyltransferase IV (FUT4) by binding directly to the FUT4 F3; this finding was validated by ChIP-quantitative PCR and a luciferase reporter assay. Ulex europaeus agglutinin I, which binds Fucα1-2Galβ1-4GlcNAc, and Lewis antigens showed decreased binding to the plasma membrane of cells that overexpressed MyoD1. Knockdown of FUT4 mimicked MyoD1 overexpression by suppressing GC cell migration and invasion; this result implied that MyoD1 suppressed cell migration and invasion via inhibiting the FUT4/matrix metallopeptidase signaling pathway. In summary, this study demonstrated that MyoD1 suppresses migration and invasion of GC cells by directly binding to the F3 region in the FUT4 Up2k and inhibiting FUT4/type II Lewis antigen expression.

Tumor microenvironment plays an important role in tumor proliferation, metastasis, and angiogenesis. Local RAS is a key factor to tumor proliferation and metastasis in NSCLC microenvironment, but its role on angiogenesis and VM formation remains unclear. Although overwhelming majority of previous studies suggested that VM is well established in aggressive tumor and facilitates tumor growth and metastasis, we put forward different views from another angle. We proved that status of tumor blood supply patterns, including VM channels and endothelial vessels, can dynamically exchange with each other along with local RAS fluctuations in microenvironment. Quantitatively, ACE2/ACEI promotes VM formation via Nodal/Notch4 activation; while structurally, ACE2/ACEI leads to a strong and solid structure of VM via inhibition of VE-cadherin internalization. These changes induced by ACE2/ACEI relate to relatively low metastasis rate and comforting prognoses of NSCLC patients.

Colorectal cancer (CRC) is one of the most common cancers worldwide. MicroRNAs (miRNAs) play a vital role in a variety of biology processes. Our previous work identified miR-139-5p as a tumor suppressor gene overexpressed in CRC that assisted in inhibiting progression of cancer. The main challenge of miRNAs as therapeutic agents is their rapid degradation in plasma, poor uptake, and off-target effects. Therefore, the development of miRNA-based therapies is necessary. In this study, we developed a cationic liposome-based nanoparticle loaded with miR-139-5p (miR-139-5p-HSPC/DOTAP/Chol/DSPE-PEG2000-COOH nanoparticles, MNPs) and surface-decorated with epithelial cell adhesion molecule (EpCAM) aptamer (Apt) (miR-139-5p-EpCAM Apt-HSPC/DOTAP/Chol/DSPE-PEG2000-COOH nanoparticles, MANPs) for the targeted treatment of CRC. The size of MANPs was 150.3 ± 8.8 nm, which had a round-shaped appearance and functional dispersion capabilities. It also showed negligible hemolysis in the blood. MANPs markedly inhibited the proliferation, migration, and invasion of one or more CRC cell lines in vitro. Furthermore, we demonstrated the uptake and targeting ability of MANPs in vivo and in vitro. MANPs inhibit the growth of HCT8 cells in vitro and have a significant tumor suppressive effect on subcutaneous HCT8 colorectal tumor mice. Our results demonstrated that MANPs were an effective carrier approach to deliver therapeutic miRNAs to CRC.

Objective: Ephedrine hydrochloride (EH) is a major component from Ephedra sinica STAPF, which is used as a traditional Chinese herbal medicine. This study was designed to investigate the effect of EH on water metabolism and further explore the relevant signaling pathway of body fluid regulation in “lung governing regulation of water passage” using a rabbit model of mechanical ventilation. The molecular mechanism of the EH effect in the kidney was also investigated. Methods: Rabbits were randomly divided into a control group, model group, EH group, and dexmedetomidine hydrochloride (DH) group. Urine volume was measured by the intubation method and pathologic changes in lung and renal tissue were measured by hematoxylin and eosin staining. Nitric oxide (NO) production in lung, serum, and kidney were analyzed using chemical methods. An ELISA was used to analyze angiotensin II (Ang II), antidiuretic hormone (ADH), prostaglandin E2 (PGE2), atrial natriuretic peptide (ANP), and endothelin-1 (ET-1) levels in the lung, serum, and kidney. Aquaporin-1 (AQP1) and aquaporin-2 (AQP2) mRNA and protein expression in the kidney was determined using qRT-PCR and immunohistochemistry. Results: EH significantly inhibited the decrease in the total urine volume in the third and fourth stages, and displayed significant regulatory effects on NO, Ang II, ADH, PGE2, ANP, and ET-1 in serum, lung, and renal tissues compared with the model group. In the kidney, AQP1 and AQP2 mRNA and protein expression in the EH group were remarkably down-regulated compared with the model group. Conclusion: EH exerted a regulatory effect on water metabolism by diffusing the lung and increased urine volume in the rabbit model, which was consistent with the decrease in kidney AQP1 and AQP2 expression levels that led to an increase in urine volume. EH could assist with DH to exert a protective effect on the clinical application of mechanical ventilation. Keywords: Mechanical ventilation, Ephedrine hydrochloride, Dexmedetomidine hydrochloride, Humoral regulation

Oxidation reaction is the typical thermal runaway reaction, and the reaction of 1, 4-dioldiacetate-2-Butene oxidized by ozone was investigated in this study. Firstly, the thermal hazards of the oxi...

During the past decades, considerable effort has been focused on the development of nitrogen-rich high-energy density compounds (HEDCs). In this research, 5-(2-pyrimidyl) tetrazole (Hpymtz), an energetic potential heterocyclic compound which may lead to serious explosions due to the thermal decomposition, was prepared from NaN3 and 2-cyanopyrimidine and characterized by IR spectroscopy. Thermokinetics characteristics of Hpymtz were studied by differential scanning calorimetry (DSC). A better approach to non-isothermal kinetics was applied to overcome the insufficiency of the traditional kinetic method, which oversimplified the process having complex behaviors. Fraser–Suzuki (FS) function was used to gain insights into reaction mechanisms and a complete kinetic description after deconvolution steps. Based on the results of the deconvolution method, kinetic parameters for two decomposition processes were obtained by Kissinger method, Ozawa method and Starink method after deconvolution steps. Self-accelerated decomposition temperature (TSADT), thermal ignition temperature (TTIT), critical temperature of thermal explosion (Tb), enthalpy of activation (ΔH≠), entropy of activation (ΔS≠), and free energy of activation (ΔG≠) were obtained by experiment data from DSC. The kinetics and thermodynamic properties serve as a theoretical basis for the production, transportation, and application of tetrazole materials.

In this paper, we exam the insulating characters of cubic ZrO2 (c-ZrO2) slabs with various possible terminations within three lower index Miller planes (001), (110) and (111). It is found that, firstly, a shift towards higher energy region makes the valence bands of both the O-terminated slabs of (001) plane and OO-terminated slabs of (111) plane of c-ZrO2 cross the Fermi level (EF) and thus unusable as a gate dielectric oxide. Second, a new splitting state presented just below the bottom of conduction band and crossed the EF imply the Zr-terminated slabs of both (001) and (111) planes of c-ZrO2 are also unusable as a gate dielectric oxide. Thirdly, combining above two mechanisms together makes the insulating character disappear completely for Zr + O-terminated slabs of the (001) plane of c-ZrO2 and thus unusable as a gate dielectric oxide. Fourth, the insulating character is maintained for both the ZrO2-terminated slabs of the (110) plane and the O-terminated slabs of the (111) plane of c-ZrO2 and thus usable as a gate dielectric oxide. We hope these theoretical predictions can provide a guide in fabrication and application of ZrO2 gate dielectric material.

The thermal decomposition characteristics and the thermal safety parameters of 2,2-di(tert-butylperoxy)butane (DBPB) was investigated by differential scanning calorimetry (DSC). The apparent activation energy (Ea) was evaluated by three different kinetic analysis methods based on the DSC experimental results. By the method of Malek, Zhuravlev-Lesokhin-Tempelman (Z-L-T) equation was the most probable mechanism function of DBPB decomposition. Furthermore, for the safety of storage and transportation, the self-accelerating decomposition temperature (SADT) of 50 kg standard packaged 50% w.t. DBPB solution was calculated by Semenov model. And the decomposition products were separated and identified by gas chromatograph/mass spectrometer (GC/MS). The decomposition process of DBPB was inferred which may help us to interpret the decomposition mechanism of di-functional peroxides. Finally, the findings of this study could do a contribution to preventing the thermal hazardous accidents, which would happen during DBPB chemical process, transportation and storage.

Thermal polymerization of styrene in a lab-scale batch reactor was simulated using computational fluid dynamics (CFD). The corresponding hydrodynamic model of thermal polymerization of styrene was combined with the fluid–solid coupling model of a simulated heat exchanger by using the CFD method to construct the corresponding reactor model. The effects of stirring rate, cooling temperature, and cooling flow rate were investigated under the runaway conditions of thermal polymerization of styrene. The results showed that the increase in temperature during the reaction was sensitive to different runaway conditions. The stirring rate and cooling flow rate greatly influenced the increase in temperature during the reaction. Based on the temperature distribution inside the reactor, the optimal location of the temperature monitor was determined by employing the divergence (DIV) criterion.

A novel tetrazole-based lead(II) complex, [PbL(H2O)] (1) [H2L = N-(1-carboxymethyltetrazole-5-yl)-N-(2′-carboxymethyltetrazole-5′-yl)amine], was prepared by solvothermal reaction. IR, single crystal X-ray diffraction (XRD), elemental analysis and thermogravimetric analysis (TGA) were used to characterize the structure of 1. Complex 1 shows a 2D network. Differential Scanning Calorimetry (DSC) was used to study the kinetic parameters and thermal hazards of 1. Starink method was adopted for isoconversional approach to determine the activation energy during the decomposition of 1. An improved method developed from Malek’s was employed in order to figure out the most probable reaction model for the decomposition process. Kinetic analysis reveals that decomposition of 1 conforms to the S-B function. Self-accelerating decomposition temperature (SADT) was also determined, indicating the temperature range for safe transportation of 1.

Thermal runaway can occur during the styrene bulk polymerization process because of easily formed local hotspots resulting from the high viscosity of reactants and the difficulty of heat dissipation. To obtain the thermal hazard characteristics, the polymerization behavior of styrene was investigated using differential scanning calorimetry (DSC) at a scanning rate of β = 2 °C/min. Experimental results showed that the exothermic peaks obtained for heat initiation were different from those obtained when initiator was added. The exothermic peak changed from one to two after the initiator was added. The exothermic onset temperature (T0) was also reduced. Phi-tech II was utilized to study the bulk polymerization of styrene in an adiabatic environment. The adiabatic temperature rise (ΔTad), starting temperature of uncontrolled polymerization (Tstar), maximum temperature (Tend), and heat of polymerization (ΔH) under different conditions were acquired. When the dose of the additive was increased, the starting temperature of uncontrolled polymerization (Tstar) decreased and the adiabatic temperature rise (ΔTad) increased gradually. Severity grading was performed based on the severity evaluation criteria of runaway reaction. The results can help designers decide whether it is necessary to take certain measures to reduce risk.

Tert-butyl peroxybenzoate (TBPB) is thermally unstable organic peroxide, which may cause disasters such as fire or explosion when excessive heat released due to thermal decomposition. Ionic liquid is often used as a catalyst and inhibitor in engineering applications recently. This study investigated the thermal decomposition characteristics of TBPB when added two different ionic liquids which are 1-Propyl-3-methylimidazolium iodide ([PMIM][I]) and 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) respectively with different mass ratio under DSC tests. Characteristic parameters such as the onset exothermic temperature (T0) and heat of decomposition (ΔHd) of samples were compared. Kinetic parameters such as activation energy Ea were computed using two isoconversional methods which were Ozawa method and Friedman method respectively. The model based (zeroth order reaction) estimation method was used to estimate TMRad at T0 from non-isothermal DSC measurements to assess the thermal hazard of five samples. The paper aims to study the effect of ionic liquids (ILs) on the thermal decomposition of TBPB and analysis the influence of two ionic liquids on the decomposition mechanism of TBPB.

Background Metal foam has been demonstrated numerous advantages in fine chemistry when used as catalyst support. In this research, a novel strategy for the fabrication of copper tungstate (CuWO4) foam as heterogeneous catalysis to conduct dimethyl sulfoxide (DMSO) oxidation reaction in a scale-up microreactor was proposed. Methods A series of three-dimensional skeleton CuWO4 foams were prepared by a continuous sintering approach. The obtained CuWO4 catalysis inherited the porous structure from the copper foam and had a high loading density of CuWO4 crystal particles. Afterwards, DMSO oxidation was employed as a probe reaction to explore the catalytic performance of CuWO4 foam. Significant findings CuWO4 foam showed prefect catalytic activity in a scale-up microreactor. The average crystallite size of CuWO4 were increased from 52.8 to 57.7 nm with extension of sintering time. Under the optimum condition (residence time was 40 min, CuWO4 catalyst was CuWO4F-5 and reaction temperature was 80 oC), a high dimethyl sulfone yield of 65.4% was obtained. The yield of MSM reached nearly 65.3% in the run time of 1 h and showed a value of 50.4% even in the run time of 4 h. Higher reaction contact surface and larger crystal particles of CuWO4 foam are conducive to enhancing the catalytic performance of CuWO4 foam. This research indicates the potential opportunity to apply CuWO4 foam in a scale-up microreactor.

Osteoporosis is a common metabolic bone disease with high prevalence. Tetrandrine (TET) suppressed osteoclastogenesis, while the roles of TET in osteoporosis regulation remained unclear. Thus, the study aimed to investigate the effect of TET on osteoporosis and the underlying mechanism.The osteoporosis rabbit model was established through anterior cruciate ligament transection (ACLT) and bilateral ovariectomy (OVX). The degeneration of articular cartilage was assessed using HE staining and Alcian blue staining. The liver and kidney tissue injury was determined using HE staining. The activity of osteoclasts was evaluated using Tartrate-resistant acid phosphatase (TRAP) staining. The changes in bone structural parameters were determined through measuring the BMD, BV/TV, Tb.Th, Tb.N, and Tb.Sp, and the serum levels of calcium and phosphorus. Macrophage polarization was determined using Flow cytometry.The bone structural parameters including BMD, BV/TV, Tb.N, Tb.Th and Tb.Sp were changed in osteoporosis rabbit, which was reversed by TET. Besides, TET suppressed the increased serum levels of calcium and phosphorus in osteoporosis rabbit. Furthermore, TET inhibited the degeneration of articular cartilage and the activity of osteoclasts induced by osteoporosis. Moreover, TET inhibited the levels of MMP-9, PPAR-γ, RANKL, β-CTX and TRACP-5b, and increased the levels of OPG, ALP and osteocalcin (OC) in osteoporosis. Additionally, TET promoted macrophage transformation from M1 to M2 in osteoporotic and inhibited the production of IL-1β, TNF-α, and IL-6. TET also inhibited the p65 phosphorylation in osteoporosis. Besides, TET reversed RANKL-induced osteoclasts proliferation, p65 phosphorylation, and the expression changes of RANKL, Ki67, PPAR-γ, ALP, OPG.TET attenuated bone structural parameters including BMD, BV/TV, Tb.N, Tb.Th and Tb.Sp, inhibited articular cartilage degeneration, promoted bone formation, inhibited the inflammatory response, and promoted macrophage transformation from M1 to M2 via NF-κB inactivation in osteoporosis. TET may be a promising drug for osteoporosis therapy.TET: Tetrandrine; ACLT: anterior cruciate ligament transection; OVX: ovariectomy; TRAP: Tartrate-resistant acid phosphatase; BMD: bone mineral density; BV/TV: Bone volume/total volume; Tb.Th: trabecular thickness; Tb.N: trabecular number; Tb.Sp: trabecular separation; MMP-9: Matrix metallopeptidase 9; PPAR-γ: Peroxisome proliferator-activated receptor gamma; RANKL: Receptor activator of nuclear factor kappa-B ligand; OPG: Osteoprotegerin; ALP: alkaline phosphatase; OC: osteocalcin; β-CTX: β isomer of C-terminal telopeptide of type I collagen; TRACP-5b: Tartrate-resistant acid phosphatase 5b; TNF-α: tumor necrosis factor-α; IL-1β: interleukin-1β; IL-6: interleukin 6; NF-κB: Nuclear factor kappa B; PKC-α: Protein kinase C alpha; qRT-PCR: Quantitative real-time polymerase chain reaction.

This study investigated the effect of methyl-CpG-binding protein 2 (MeCP2) on miRNA transcription. Our results of miRNA chip assay and ChIP-seq showed that MeCP2 inhibited the expressions of numerous miRNAs by binding to their upstream elements, including not only the promoter but also the distal enhancer. Among the affected miRNAs, miR-22 was identified to remarkably suppress gastric cancer (GC) cell proliferation, arrest G1–S cell cycle transition, and induce cell apoptosis by targeting MeCP2, MTHFD2, and MTHFR. Understanding GC metabolism characteristics is the key to developing novel therapies that target GC metabolic pathways. Our study revealed that the metabolic profiles in GC tissues were altered. SAM (S-adenosylmethionine), a universal methyl donor for histone and DNA methylation, which is specifically involved in the epigenetic maintenance of cancer cells, was found increased. The production of SAM is promoted by the folate cycle. Knockdown of MTHFD2 and MTHFR, two key enzymes in folate metabolism and methyl donor SAM production, significantly suppressed GC cell proliferation. MiR-22 overexpression reduced the level of endogenous SAM by suppressing MTHFD2 and MTHFR, inducing P16, PTEN, and RASSF1A hypomethylation. In conclusion, our study suggests that miR-22 was inhibited by MeCP2, resulting in deficiency of endogenous SAM, and ultimately leading to tumor suppressor dysregulation.

Methyl-CpG-binding protein 2 (MeCP2) facilitates the carcinogenesis and progression of several types of cancer. However, its role in breast cancer and the relevant molecular mechanism remain largely unclear. In this study, analysis of the Cancer Genome Atlas (TCGA) data that MeCP2 expression was significantly upregulated in breast cancer tissues, and high MeCP2 expression was correlated with poor overall survival. Knockdown of MeCP2 inhibited breast cancer cell proliferation and G1–S cell cycle transition and migration as well as induced cell apoptosis in vitro. Moreover, MeCP2 knockdown suppressed cancer cell growth in vivo. Investigation of the molecular mechanism showed that MeCP2 repressed RPL11 and RPL5 transcription by binding to their promoter regions. TCGA data revealed significantly lower RPL11 and RPL5 expression in breast cancer tissues; additionally, overexpression of RPL11/RPL5 significantly suppressed breast cancer cell proliferation and G1–S cell cycle transition and induced apoptosis in vitro. Furthermore, RPL11 and RPL5 suppressed ubiquitination-mediated P53 degradation through direct binding to MDM2. This study demonstrates that MeCP2 promotes breast cancer cell proliferation and inhibits apoptosis through suppressing RPL11 and RPL5 transcription by binding to their promoter regions.

Phenotypic plasticity is an important adaptation to spatial and temporal environmental variations. For submerged macrophytes, adaptation to water depth and light variation is particularly important. To determine the morphological and physiological adaptive strategies of Vallisneria natans at different water depths and light conditions, we combined field investigation, light control experiment and in situ physiological response experiment. In the field investigation and the light control experiment, both water depth and light intensity had prominent effects on the morphological of V. natans, especially in fresh weight and leaf length. The leaf length elongated more rapidly at intermediate water depth sites with lower light intensity. In the in situ experiment, the survival boundary of V. natans is 5.5 m in Lake Erhai. Below this depth, the chlorophyll-a content increased gradually with increasing water depth. Our results demonstrated that V. natans can adapt to water depth and light availability by changing morphological, physiological and resource allocation. At low light condition, V. natans invested more resource for light acquisition, simultaneously, changing the photosynthetic pigment content to compensate for light attenuation; conversely, more resource was directed towards reproduction. These results will provide new insight for species selection when conducting aquatic plants restoration in freshwater ecosystem.HIGHLIGHTSWater depth and light availability affect the morphology, physiology, and resource allocation of V. natans.An alternative resource allocation pattern of V. natans could shift between light acquisition and reproduction.

A novel nanofiltration membrane bioreactor (NF-MBR) was constructed by integrating a loosely structured nanofiltration hollow fiber membrane into an aerobic activated sludge system. In order to verify the feasibility of loose NF membrane bioreactor, parallel experiments of conventional ultrafiltration membrane bioreactor (UF-MBR) and NF-MBR were conducted to investigate process performances, membrane fouling characteristics. The loose NF membrane showed a relatively high permeability at a level of around 10 L m-2 h-1 bar-1 (flux of 2.0 L m-2 h-1) under low operation pressure (10–30 KPa). The results showed that NF-MBR achieved a higher removal efficiency of chemical oxygen demand (CODCr) and dissolved organic carbon (DOC) due to high rejection of loose NF membrane for biopolymers and part of the humic substances. During long term operation in NF-MBR, loose NF membrane displayed low salt rejection, resulting in no obvious salts accumulation in bioreactor in comparison with UF-MBR. The average rising rates in TMP for the NF-MBR was 0.16 KPa/day, which was twice lower than that of UF-MBR. The results of fouling mechanism showed that reversible cake fouling was dominant for both NF and UF membranes, while the relatively small pore size of the NF membrane mitigated irreversible pore blockage. Further biofouling layer analysis demonstrated that humic substances, polysaccharides and proteins were the main organic foulants. The results of energy consumption revealed that NF-MBR had comparable total energy consumption compared with UF-MBR. The outcomes of this study show the feasibility of loose NF membrane bioreactor to provide a great potential as an advanced process for wastewater treatment.

Microreactors have been widely used with advantageous of large specific surface area, excellent heat and mass transfer performance. In this paper, experimental and numerical study were carried out to analyze the thermal hazard associated with the synthesis of isopropyl propionate in a microreactor. In the experimental study, the effects of reaction temperature, catalyst amount, channel diameter and flow rate were investigated. The optimal condition was as follows: channel diameter 2 mm, amount of catalyst 0.8%, reactant ratio n(propionic anhydride): n(isopropanol) = 1:1, flow rate V (propionic anhydride + isopropanol) = 1 ml/min, and reaction temperature T = 60 °C. In this condition, the conversion of propionic anhydride reached 89.9% and the space–time yield was 2.39 × 10 6 mol ⋅ m−3 ⋅ h−1. Computational Fluid Dynamics (CFD) technology was used to develop a model of the microreactor with this optimum condition. It showed that the flow rate of coolant and material of the microreactor had a great influence on the distribution of temperature. A lower cooling flow rate would lead to the formation of a heat transfer barrier in the cooling jacket. Under the same condition, a silicate glass microreactor had better heat transfer performance and was safer than other options.

Esterification reactions between anhydrides and alcohols catalyzed by sulfuric acid have broad applications in the food, cosmetic, and pharmaceutical industries. However, the exothermic behavior cannot be well explained, especially in semibatch reactors with different feeding procedures. In this study, a series of esterification processes in semibatch systems were conducted with a wide range of feeding rates with two different substrates. The structures of initial catalytic substrates were characterized using in situ Fourier Transform Infrared (FTIR) spectroscopy. A total of 11 reaction pathways, including those for the initial activation of substrates and the subsequent reactions of the feeding process, were calculated by the density functional theory (DFT) method. Three possible catalytic cycles of the esterification with specific acid catalysis, protonated intermediate, and protonated intermediate and H2O, were established for the semibatch esterification reaction based on calculated results and experimental evidence. Thermal safety parameters such as reaction enthalpy ( Δ H r ), adiabatic temperature rise ( Δ T r , a d ), and maximum temperature of the synthetic reaction (MTSR) were determined based on Wilson equation used to calibrate mixing heat. The results reveal that mixing heat was 2.5 kJ/mol with same mole ratio of n-butanol (nB) and propionic anhydride (PA). The reactions started by PA are dominant, no matter whether the substrate is nB or PA. The initial reaction rate is restricted by the low concentration of catalyst and active reactant when nB is used as substrate, which lead to significant reactant accumulation with high MTSR of approximately 160 °C. Furthermore, feeding nB into PA allows a controllable increase in the Δ T r , a d realized by changing the feeding rate and limiting the accumulation of reactant.

Since wear usually occurs on the surface, it is not necessary to fabricate self-lubricated bulk materials. In the paper, Ti(C,N)-based cermets with self-lubricated gradient surfaces are prepared after carburizing treatment based on W-doped carbon-deficient cermets. The microstructures, mechanical properties and wear behavior of the W-doped self-lubricated Ti(C,N)-based cermets were investigated. The results showed that when W is added into the cermets, the carbon-deficient cermets were prepared. This carbon-deficient system hinders the inward immigraion of carbon atoms and thus changes the distribution of other elements in the cermets which results in the formation of a gradient layer enriched in graphite phase but deficient in Ni binder phase. Besides, with the increase of W content, the amount of graphite decreases. Moreover, the TRS and the hardness of cermets is enhanced due to the addition of W and the hardness of the graded cermets was obviously different along the depth direction. Compared with the self-lubricated bulk cermets without the addition of W, the self-lubricated cermets with 2 wt% W addition show the best tribological properties due to the lubricated effect of the gradient layer with high volume fraction of graphite as well as a superior tough substrate.

Sm2/3Cu3Ti4O12 ceramics with giant dielectric constant were successfully prepared by the traditional solid-state sintering process. The dielectric characteristics and relevant mechanism were systematically investigated. The dielectric constants of Sm2/3Cu3Ti4O12 ceramics can reach to 104 at 298 K and 1 kHz, and also exhibited two distinct thermal-activated dielectric relaxations in different temperature ranges. The dielectric relaxation at low temperatures was regarded as the effect of the polyvalence structures (Cu2+/Cu3+ and Ti3+/Ti4+) in grains due to the oxygen compensation during the sintering process, while the dielectric relaxation at high temperatures was induced by the grain boundary effects. The giant dielectric response in Sm2/3Cu3Ti4O12 ceramics can be associated with the heterogeneous structure and combined effect of the grain and grain boundary.

An ultraviolet (UV) photodetector based on ZnO-reduced graphene oxide (ZnO-rGO) composites have been successfully fabricated. A pure ZnO photodetector was also fabricated by similar method. In comparison with the pure ZnO UV photodetector, the ZnO-rGO photodetector exhibits a much larger photocurrent and a better light-to-dark-current-ratio. The mechanism of photocurrent enhancement was investigated using I-V characteristics, photoluminescence (PL) spectra, transmittance spectra and time-dependent photocurrent analysis. Results show that the photocurrent enhancement of the ultraviolet photodetector is due to the improvement of the carrier lifetime, because the carrier recombination of ZnO were reduced by rGO. It provides a potential way to fabricate high-response UV photodetectors.

Dust deposition on photovoltaic (PV) modules is related to environmental and weather conditions and results in a reduction in power generation efficiency over time. The effects of films on the transmittance can be obtained by testing sample glasses coated with silicon and fluorine super-hydrophobic films with a spectrophotometer. Red soil particles with a diameter of 25 μm were selected to simulate the process of natural dust deposition on PV module samples, and an incubator of constant temperature and humidity was used to simulate the condensation process. PV module samples were irradiated by a solar simulator after the aforementioned simulation process, and the effects of different amounts of sediment in unit areas on the photovoltaic properties and spectral characteristics were determined. The experimental results indicate that the influence of dust on the power generation efficiency of PV modules coated with fluorine super-hydrophobic film is smaller than that for PV modules coated with silicon super-hydrophobic film and that the super-hydrophobic films can not only greatly reduce the dust accumulation on the surface of PV modules but also increase the generating efficiency.

A novel multicyclo-tetrazoles energetic material, 1,3,3,5-tetra(1H-tetrazol-5-yl)-pentane (TTZP), was prepared by 1,3,3,5-tetra(cyano)-pentane and sodium azide. The crystal structure is characterized by X-ray diffraction. The thermal stabilities and the kinetic parameters of TTZP were studied by differential scanning calorimetry (DSC) and adiabatic calorimetry (Phi-TEC). Starink method was employed to calculate the activation energy based on the DSC data. Due to the complex reaction mechanism, the traditional method for the adiabatic data which using an nth-order reaction was modified based on the Kinetics Committee recommendations of the International Confederation for Thermal Analysis and Calorimetry. Avrami–Erofeev equation which was selected for the adiabatic simulation has good performance on the calculation of activation energy and pre-exponential factor. Finally, the important safety parameters (self-accelerating decomposition temperature) was calculated and discussed.

The pyrolysis characteristics of tetrazolo[1,5-a]pyridine were investigated by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). The apparent activation energy (Eα) was estimated with DSC and various kinetic analysis methods, and it was determined that the decomposition of tetrazolo[1,5-a]pyridine follows the Avarami-Erofeve (A2) reaction pattern. The thermal safety and thermodynamic parameters were calculated. In addition, the thermal runaway behavior and kinetic parameters under adiabatic conditions were studied by employing an adiabatic accelerating calorimeter (ARC). Thermogravimetric-photoionization mass spectrometry (TG-MS) was used to identify the vapor phase products of the pyrolysis process. The different decomposition pathways were analyzed by density functional theory (DFT). The main decomposition products were N2, C2H2 and HCN according to TG-MS experiments and theoretical calculations. The most likely proposed decomposition mechanism proceeded through the opening of the tetrazole ring to dissociate N2 and the rupturing of the pyridine ring to release C2H2 and HCN. The findings of these experiments and theoretical calculations can contribute to the determination of safety precautions for possible heat hazard accidents during the handling, transportation, use and storage of tetrazolo[1,5-a]pyridine.