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This paper uses ANSYS Workbench platform to simulate the casting and rolling composite process, taking the horizontal type casting and rolling machine as the research object, and conducts the numerical simulation study of copper-aluminum composite solid-liquid casting and rolling heat-flow coupling, mainly to study different walking speed, aluminum pouring temperature, casting and rolling zone length, heat transfer coefficient on the temperature field, liquid phase rate influence law, and use it as a theoretical guide for copper-aluminum solid-liquid casting. The experiments of copper-aluminum solid-liquid casting-rolling composite were carried out to optimize the process parameters and to verify the experiments, so as to prepare a well-bonded copper-aluminum composite plate. The composite mechanism in the preparation of copper-aluminum composite plate was analyzed, and it was clarified that the interfacial layer was formed through four stages: contact between copper and aluminum surfaces, contact surface activation, mutual diffusion of copper and aluminum atoms, and reaction diffusion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zn1 and Zn2 have a monomer or dimer structure and are stable in buffer solution. • Zn1 and Zn2 hve excellent anti-tumor activity to A549 cells inducing apoptosis through the mitochondrial pathway. • Zn1 and Zn2 could inhibit the migration of A549 cells well. • Zn1 and Zn2 inhibit tumor growth without causing significant toxicity in organs. Two acylhydrazone based zinc(II) complexes [Zn(HL) 2 Cl 2 (CH 3 OH) 2 ] (Zn1) and [ZnL(AC)] 2 (Zn2) were synthesized from 3-(1-(salicyloylhydrazono)ethyl) pyridine (HL). Single crystal X-ray structure analyses showed that complexes Zn1 and Zn2 have a zero-dimensional monomer or dimer structure. Antiproliferative activity studies revealed that Zn1 and Zn2 are both more effective against A549 cells than cisplatin. The results of the reactive oxygen species (ROS) generation assay on A549 cells showed that both Zn1 and Zn2 induced apoptosis through ROS accumulation. The apoptosis-inducing and cell cycle arrest effects of Zn1 and Zn2 on A549 cells indicated that the antitumor effect was achieved through apoptosis induction and inhibition of DNA synthesis by blocking the G 0 /G1 phase of the cell cycle. What's more, the results of wound-healing assay showed that Zn1 and Zn2 could inhibit the migration of A549 cells. Western blot analysis further demonstrated that Zn1 and Zn2 induced cell apoptosis through the mitochondrial pathway, in which process, the expression level of cytochrome C , cleaved-PARP, cleaved-caspase 3 and cleaved-caspase 9 proteins increased while pro-caspase 3 and pro-caspase 9 expression decreased. In vivo anticancer evaluation demonstrated that both Zn1 and Zn2 complexes effectively inhibited tumor growth without causing significant toxicity in systemic organs. [ABSTRACT FROM AUTHOR]

(We could not place the transducer and the left leg electrode on the pulsation at the same time and thus were unable to directly compare the arterial pulse waveform with other electrocardiogram leads.) C. Synchronous recordings of electrocardiogram lead I and the arterial pulse waveform in the left leg. All the limb leads and precordial leads depend on the left leg electrocardiogram electrode, except for lead I. As a result, we examined the left leg electrode and felt a strong pulsation that we interpreted as arterial pulsation. [Extracted from the article]

The structural evolution of SF-soot (derived from the rapid pyrolysis of ShenFu bituminous coal) and a carbon black (Printex) was performed for air oxidation at 1273 and 1473 K. The morphology and nanostructure transformations were examined at conversion fractions ~0.2, 0.4, 0.6, and 0.8. Three modes of behavior were evident. The behavior of SF-soot followed an internal oxidation model (IOM) at 1273 K. The oxygen was able to fully permeate into the particle core, producing a sphere with variable removal of the interior structure with conversion. However, at the higher temperature, the SF-soot formed a concentric spherical structure with gradual consumption of the inner sphere due to restricted oxygen penetration. The fragmentation of hollow interior particles, on which the available literature is not extensive , was observed from HRTEM and SEM micrographs for the first time. During the oxidation of SF-soot, micropores were mainly generated during the 0–0.2 conversion, while the mesopore surface rapidly increased during the 0.6–0.8 conversion. The X-ray diffraction (XRD) patterns and Raman spectra both show that the oxidation of SF-soot is mainly a disordering process. The graphitic microcrystals were mainly consumed along the longitudinal orientation during the 0–0.2 conversion but were mainly consumed along the horizontal during the 0.4–0.8 conversion. The true densities of SF-soot and carbon black initially increase and then decrease monotonically during oxidation. [ABSTRACT FROM AUTHOR]

Chrysomya bezziana is an obligate, myiasis-causing fly in humans and warm-blooded animals throughout the tropical and subtropical Old World. We report a case of cutaneous myiasis due to C. bezziana in a dog from Guangxi province in China. A total of 35 maggots were removed from the lesions. Direct sequencing of the mitochondrial cytochrome b gene showed that the specimen belonged to haplotype CB_bezz02, which was previously reported in Malaysia and the Gulf region. This paper also reviews reported cases of screwworm myiasis from humans and animals in China. Geographical records indicate that the distribution of C. bezziana is expanding, suggesting that an integrated pest management control should be taken into consideration in China. [ABSTRACT FROM AUTHOR]

Abstract The present work aims to investigate the effects of a CO 2 -rich atmosphere on the characteristics of coal-derived soot. The rapid pyrolysis of Shenfu bituminous coal was conducted in a Drop tube furnace (DTF) in N 2 and CO 2 atmospheres with a wall temperature of 1073–1473 K and residence time below 700 ms. The yields and microstructure characteristics of N 2 -soot and CO 2 -soot were analysed by using a series of techniques (elemental analysis, HRTEM, Raman, XRD, FT-IR and thermogravimetry techniques). CO 2 enhanced the soot formation and proceeded the dehydrogenation. CO 2 improved the order of internal carbon lattices, enhanced the lateral extension of carbon nanostructures, decreased the interplanar spacing of the graphene layers and also promoted the stack of polyaromatic layers. The variations of the SOLO, DUO, TRIO and QUARTO structures were also analysed, and the contribution of CO 2 was found to reduce the defects of the basic structure units (BSU). The defects of soot were an important indication of the initial gasification reactivity. Overall, CO 2 -soot was more mature and low active than N 2 -soot. [ABSTRACT FROM AUTHOR]

Supplemental Digital Content is available in the text. [ABSTRACT FROM AUTHOR]

In this study, an upgrading process of lignite with supercritical CO 2 extraction under rather mild temperatures was studied as a possible method for producing clean solid fuel with less moisture and enhanced combustion reactivity. The fractal characteristics and reactivity evolution of two typical lignites during the upgrading process by supercritical CO 2 extraction have been studied in present work. Two typical lignites and one subbituminous coal were extracted in different conditions by a semi-continuous supercritical CO 2 extraction device and the evolution of coal pore structure was investigated by N 2 and CO 2 adsorption/desorption isotherms. Two fractal dimensions D 1 and D 2 , at relative pressures 0–0.45 and 0.45–1, respectively, were calculated by the Frenkel-Halsey-Hill model. The combustion reactivity of raw and upgraded coals was studied by a thermogravimetric analyzer. The results indicate that the N 2 quantity adsorbed in pores of upgraded lignite increases with the increase of extraction time and temperature which is consistent with the variation of specific surface area and total pore volume of upgraded lignite. The mesopores and micropores of upgraded HB lignite are developed whereas macropores and mesopores of upgraded ZT lignite are enlarged after supercritical CO 2 extraction. It was found, D 1 values of upgraded HB lignite decrease whereas D 2 values increase slightly. Meanwhile, the D 1 and D 2 values of upgraded ZT lignite are all decreased. The D 1 values are mainly affected by the influence of mesopores and macropores on specific surface area and D 2 values are mainly affected by the effects of fine mesopores and micropores on total pore volume. We found that D 1 values have a positive relationship with the average pore diameter whereas have a negative relationship with specific surface area and total pore volume. D 2 values have a negative relationship with average pore diameter whereas have a positive relationship with specific surface area and total pore volume for the raw and upgraded lignite. The combustion reactivity of upgraded lignite is enhanced after supercritical CO 2 extraction due to the improvement of specific surface area and total pore volume. [ABSTRACT FROM AUTHOR]

Fine particles formed during pyrolysis are the precursors of particulate matters (PM) after combustion and/or gasification. This study aims to conduct a preliminary research on the characteristics of fine particles. The rapid pyrolysis of raw and acid-washed biomass was conducted in a drop tube furnace (DTF) with a wall temperature 1073–1473 K and varied residence times. Components of fine particles formed during rapid pyrolysis were determined by investigating their morphologies and element contents. Particle size distributions (PSDs) of fine particles were also measured by granulometry technique. The results showed that the yields of fine particles increased significantly with increasing pyrolysis temperature. PSDs of fine particles formed at different conditions varied from each other, and trimodally distribution was identified for fine particles derived from pyrolysis of raw biomass at 1473 K. Those independent fine particles consisted of abundant small fragments, and slight soot and ash particles. The size of soot and melting ash particles increased with residence time and temperature, and the size ranges of small fragments broadened as residence time increased. [ABSTRACT FROM AUTHOR]

In this study, the drying characteristics and kinetics of two typical lignites were investigated by using supercritical carbon dioxide (SCCO 2 ) at mild temperature (62–102 °C). The drying characteristics results show that SCCO 2 extraction drying has advantages over conventional drying such as better heat transfer and faster diffusion rate. Seven previous thin-layer models and a new proposed model were applied to analyze the lignite drying kinetics, and the proposed model obtained the best fit to the lignite drying process in all of the models. Apparent diffusion coefficients of moisture in SCCO 2 drying are higher compared with conventional drying method. The activation energies for the diffusion process of two typical lignites are 10.5561 and 11.6218 kJ/mol, which are far lower in comparison to conventional drying process. The pore structure and gasification reactivity of drying lignite were analyzed and both of them have an obvious improvement after the SCCO 2 drying process. [ABSTRACT FROM AUTHOR]

Rapid pyrolysis of Shenfu bituminous coal was conducted with a wall temperature 1073–1473 K and residence time 0–750 ms in both CO 2 and N 2 atmospheres to study the pyrolysis mechanism in CO 2 atmosphere. The interest was focused on mass loss, gas yield, element content of chars and a series of chemical structure parameters (CH 2 /CH 3 , H ar / H , f a and (R/C) u ) obtained by FT-IR analyses. The results show that varied impacts dominated on pyrolysis at different temperatures in CO 2 atmosphere. Mass loss decreased at 1073 K but increased at 1273 and 1473 K. Both heterogeneous reaction of CO 2 with char and homogeneous reactions of CO 2 with volatile occurred during pyrolysis in CO 2 atmosphere. The combined effect of enhanced polycondensation of aromatic rings and C-CO 2 reaction has been found to increase the mass loss of char. More H-containing free radicals generated during polycondensation, which consequenctly increase combination possibility with other radical fragments to inhibit the cross-linking reaction. [ABSTRACT FROM AUTHOR]

Three metal complexes [CuL(NO3)]n (1), [Cd(HL)(NO3)2]n (2) and [EuL(HCOOH)(H2O)(NO3)2] (3) were synthesized with a pyridyl Schiff ligand L (N′-[(1E)-pyridin-2-ylmethylidene]pyridine-4-carbohydrazide). A crystallographic study revealed that complexes 1 and 2 have a chain structure, and complex 3 is a zero-dimensional monomer. In vitro cytotoxicity studies showed that complex 2 had the best antiproliferative activity against SMMC-7721 cells and complex 3 had the best antiproliferative activity against MDA-MB-231 cells with single-digit IC50 values, both exceeding those of the control drug cisplatin by far. The cell invasion and migration ability through the transwell assay and wound-healing assay showed that the selected complexes could inhibit the invasion and migration of cancer cells. The Hoechst staining assay and ROS generation assay with SMMC-7721 cells indicated that the cytotoxic effects of complex 2 involved apoptosis induction through ROS accumulation. The apoptosis-inducing and cell cycle arrest effects of complex 2 on SMMC-7721 cells indicated that the antitumor effect was achieved through apoptosis induction and inhibition of DNA synthesis by blocking the G0/G1 phase of the cell cycle. In addition, complex 2 showed significant inhibition against B. dysentery with an inhibition circle diameter of 24 mm. [ABSTRACT FROM AUTHOR]

Three metal–organic frameworks [CdL(DMF)]n1, {[CuL(H2O)(DMF)]·DMF·0.5H2O}n2, and [Nd(HL)L(DMF)3]n3 have been synthesized with a nitrobenzene derivative 4-((5-hydroxy-2,4-dinitrophenoxy)methyl)-3-nitrobenzoic acid (H2L). Compound 1 has a dense three-dimensional framework with 1D Cd chains within the framework. Compound 2 features a chain structure which is further connected by π–π interactions and intermolecular hydrogen bonds to form a 3D network. Compound 3 is a lanthanide-based metal–organic framework which also features a 3D network. Compound 1 shows low sensitivity and high stability with an intense exothermic process at 295.1 °C. The constant-volume combustion energy and impact sensitivity were measured and the heat of detonation, detonation velocity, and detonation pressure were calculated for 1, which illustrate that 1 could be applied as a potential explosive. In addition, the non-isothermal kinetics for 1–3 was studied by Kissinger's and Ozawa–Doyle's methods. The apparent activation energies of 1–3 were 167.950 kJ mol−1, 191.465 kJ mol−1, 120.060 kJ mol−1, respectively. [ABSTRACT FROM AUTHOR]

• Evolution of morphology and nanostructure of soot and carbon black during CO 2 gasification were investigated. • Three gasification modes were observed for soot and carbon black. • Here soot nanostructure transformed from ordered to less ordered during gasification. • The conversion took place both on the surface and within the core after pore formation and expansion. • The crystallites were preferentially consumed along the graphitic edges for coal-derived soot. The morphology and nanostructure evolution during gasification was examined for a coal-derived soot and, to permit comparisons to other research, two carbon black samples. The investigation examined four different conversion extents at 1273 and 1473 K. The primary particle diameter decreased significantly during the initial stage and then changed slowly. The gasification behavior varied with the initial nanostructure and treatment temperature. At 1273 K the consumption behavior followed a hybrid mode comprised of shrinking core and homogeneous reaction models. However, at 1473 K, a previously unobserved gasification behavior occurred with the soot forming concentric spheres. Here the gasification progressed by initially forming micropores, followed by insufficient permeation of oxidant with the subsequent consumption of the core, ultimately forming hollow particles. Raman spectra and X-ray diffraction patterns indicated there was a transformation from initially ordered to less well-ordered structure. Partial gasification induced disordering to different extents, accompanied by a slight maturing associated with thermal annealing. The crystallites were preferentially consumed along the graphitic edges for coal-derived soot. At the start of gasification, the density of the soot increased but subsequently declined. Abundant micropores with multimodal distributions were newly generated and continually developed during gasification. [ABSTRACT FROM AUTHOR]

Ferroptosis is a new form of cell death that relies on iron and involves an imbalance of intracellular reactive oxygen species (ROS), which is expected to help alleviate bottlenecks in tumor treatment. Herein, a sorafenib‐loaded folic acid‐armored iron‐based nMOF was designed for synergistic inducing ferroptosis of tumors. The particle size of the synthesized SM@F is about 210nm, and the drug loading rate is 24.74%. SM@F can be degraded and releases sorafenib and iron ions slowly, resulting in intracellular drug release and iron overload after being highly uptaken by SMMC‐7721 cells. SM@F can effectively inhibit the proliferation of SMMC‐7721 cells, and this effect can be significantly attenuated by ferroptosis inhibitors. Mechanistic investigations revealed that SM@F could increase the content of ROS, and lipid peroxides; decrease the content of glutathione (GSH); and down‐regulate the GXP4 expression in SMMC‐7721 cells. The results indicate that the synthesized SM@F could effectively inhibit the proliferation of tumor cells with synergistic inducing ferroptosis. [ABSTRACT FROM AUTHOR]

• Four acylhydrazone based complexes with low dimensional structures were synthesized. • Their antitumor activity to SMMC-7721, MDA-MB-231 and A549 cells was evaluated. • Complex 1 had the best activity against SMMC-7721 cells, and 2 showed the strongest effect against MDA-MB-231 and A549 cells. • The cell death mechanism of complex 2 to MDA-MB-231 cells is the induction of apoptosis generation. • Complexes 1 and 2 were both able to exhibit inhibition of the cell invasion and metastasis at very low doses. Four acylhydrazone based complexes [TbL(CH 3 OH)(H 2 O) (NO 3) 2 ]·0.32H 2 O (1), [ML(NO 3)] n M = Pb for (2), M = Zn for (3) and [Ni(HL)(H 2 L)] · (NO 3) 3 (4) (HL = N'-(pyridin-2-ylmethylene)isonicotinohydrazide) with low dimensional structures were synthesized. Crystallographic study reveals complexes 2 and 3 have a chain structure, while complexes 1 and 4 are both zero-dimensional monomers. The anti-proliferative activity showed that complex 1 had the best activity against SMMC-7721 cells, while 2 showed the strongest effect against MDA-MB-231 and A549 cells. The increase in intracellular reactive oxygen species (ROS) production and the change in cell nuclear morphology of MDA-MB-231 after treatment with 2 indicate that the cell death mechanism is the induction of apoptosis generation. Cell cycle assay with MDA-MB-231 cell showed that complex 2 was able to block the cell cycle at the G 0 /G 1 phase. In addition, the results of wound-healing and transwell assays revealed that 1 and 2 were both able to exhibit inhibition of the cell invasion and metastasis at very low doses. [ABSTRACT FROM AUTHOR]

We reported a case about the slow heart rate and regular heart rhythm that appeared after administration of digitalis, diuretics and potassium in a patient with chronic atrial fibrillation ten years. ECG characteristics demonstrated the special changes about hyperkalemia as follows: f waves disappeared; nonspecific widened QRS complex appeared; RR interval was regular; and heart rate slowed. T wave inversion reverted to be symmetrical and peaked. Laboratory investigations were noteworthy for serum potassium elevations (serum potassium was 8.50 mmol/L). In patients with chronic atrial fibrillation, digitalis administration, diuretic therapy and potassium supplementation can induce slow heart rate and regular heart rhythm. These changes may permit prompt recognition of overt digitalis toxicity-atrioventricular block. However, these have also frequently been seen in the setting of chronic renal insufficiency, resulting in hyperkalemia. The basic principles of treatment were different in these two conditions. Therefore, ECG and laboratory investigation should draw a clinician's attention. [ABSTRACT FROM AUTHOR]

• The rapid hydropyrolysis behavior of pulverized bituminous coal in a drop-tube furnace (DTF) was studied. • Hydrogen significantly improved the yield of methane when the temperature was below 900 °C. • Hydropyrolysis increased the content of naphthalene in tar and promoted the degree of lightening of tar. • Hydropyrolysis at 950 °C resulted in low graphite content char suitable for gasification. • The char from hydropyrolysis has a higher condensation degree structure and higher saturation. This paper aims to investigate the hydropyrolysis behavior of pulverized bituminous coal in a drop-tube furnace (DTF) with a temperature of 800–1000 °C. The effects of temperature and hydrogen on the compositions (gases and tar) and the structure of products (char) were investigated. Hydropyrolysis between 800 and 1000 °C resulted in a high yield of methane, and tar production decreased with increasing temperature. Besides, the light components of tar, especially the naphthalene, were significantly increased with hydrogen. The methane yield firstly increased to a peak value of 72.83 ml/g(air-dried coal) at 900 °C and then decreased with increasing temperature during hydropyrolysis. Hydrogen significant improved the yield of gaseous hydrocarbon (C 2 H 2 , C 2 H 4 , and C 2 H 6) when the temperature below 900 °C, while rarely change that at a higher temperature. At the temperature above 900 °C, the content of graphite in the hydropyrolysis char was lower than that of pyrolysis char in nitrogen. The graphite contents in the char decreased to a minimum at 950 °C and then gradually increased with increasing temperature. The char from hydropyrolysis has a higher condensation degree structure and higher saturation. The small aromatic molecules transformed into large aromatic molecules with increasing temperature under both pyrolysis and hydropyrolysis. [ABSTRACT FROM AUTHOR]

In order to study the primary fragmentation behavior of coals and biomasses, experiments of rapid pyrolysis were carried out. This work focused on the devolatilization and fragmentation characteristics including the solid/gas yield, particle density/morphology, particle size and fragmental probability ( S f ). The effects of temperature, time and solid property were investigated. The viscous flow model was employed to characterize the pressure difference (Δ P ), which was considered as the driving force of diffusion and fragmentation. The Ohm principle was used to establish the linear relation of devolatilization rate and fragmentation rate. The result showed that temperature and time have positive contribution to the fragmentation. The occurrence of fragmentation was observed more apparently with the decreasing of the ash content in the biomass. The pressure difference has a positive correlation with the fragmental rate, which shows the validity of application Ohm principle in the prediction of fragmenting process. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 71-year-old man who was diagnosed with QRS complex tachycardia after being referred to a hospital due to recurrent symptoms of syncope and palpitation. It mentions that the patient was diagnosed with electrocardiogram (ECG) suggesting that the method's comparative analysis in wide QRS complex tachycardia and sinus rhythm could help in differential diagnosis.