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The aim of this study was to investigate the properties of an organic binder used in cold-bonded briquettes (CBBs) prepared from two different iron bearing materials. The applied binder is a type of starch as indicated by chemical analysis, iodine-starch staining and Fourier transform infrared analyses. Thermogravimetric differential scanning calorimetry showed that the binder pyrolysis undergoes four stages: moisture desorption, ash volatilization, pyrolysis of organic matter and decomposition of materials with high activation energy. The difference between the dry and heat-treated samples during the macroscopic failure process is the instability propagation of the crack. The CBB shows a low decrepitation index at 700 °C. The returned fines of CBBs used with the organic binder were applied in two blast furnaces. The industrial trials showed that the CBBs do not influence the performance of the blast furnace and can reduce the fuel consumption rate. The curing rate of the binder decreases, and the growth rate of compressive strength decreases during the curing process. Iron ore particles are bonded together and exist in the form of aggregation after mixing with water and binder. The edges and corners of the particles become blurred, and the original surfaces of the particles are covered with binder film, the surface of which is covered with fine particles. The multi-branched structure of amylopectin provides omnibearing adhesion sites, thus forming binder agglomeration and film leading to a strong adhesion between binder and iron ore particles. Binder film and binder agglomeration work together to make the CBB perform well.

Wettability in unconventional reservoirs is poorly understood. However, it plays a fundamental role in fluid-rock interactions, and an understanding of wetting behavior is essential for capillary seal assessments and hydrocarbon reserve estimation and recovery in clay-rich reservoirs. In this study, the wetting behavior of transitional Shanxi-Taiyuan shale from the southern North China basin was examined via the contact angle (CA) and spontaneous imbibition (SI) measurement methods. Under water-air-shale conditions, water-wet and neutral-wet behaviors were observed, whereas neutral-wet and oil-wet behaviors were observed under water-oil-shale conditions (Young's equation was used to convert the water-air-shale system to the water-oil-shale system). When the CA method was used, the shale was shown to be hydrophobic, whereas when the SI test was used, the shale was observed to be hydrophilic. The water-air CAs are negatively correlated with the total organic content (TOC), carbonate and clay mineral contents (excluding those of illite). Furthermore, iron-containing compounds, such as pyrite and siderite, were shown to decrease the water wetness. A linear negative correlation was found between the surface roughness and the CA value. The relationship between these parameters can be used to predict the CAs at different surface roughness values for a given sample. The contradictory wetting behaviors between the results of SI and CA methods can be explained by: (i) differences between the CAs formed under water-air-shale conditions and those formed under hydrocarbon-brine-shale conditions; (ii) differences in the surface roughness, which is dependent on the texture and mineralogy of the shale sample; and (iii) clay swelling after water sorption and the formation of microfractures due to water–rock interactions.

The variation in pore water distribution within gas shale reservoirs has a significant effect on gas content, and thus on resource evaluation. However, the characteristics of water micro-distribution and its effects on pore parameters are still not well understood due to the mixed wettability of shale and the complexity of the pore structure. In this study, six lower Permian transitional shale samples from the southern North China Basin, humidified at four levels up to a relative humidity of 98%, were selected for moisture-equilibrated experiments and low-pressure N2 gas adsorption measurements. The results indicate that the adsorbed moisture in transitional clay-rich shales can be divided into capillary condensation water in the micropores and monolayer–multilayer adsorbed water in the non-micropores. Moreover, thermal maturity (VRo), total organic carbon, clay, and carbonate are positively correlated with the adsorbed moisture and micro-/mesopores, indicating that water in shales could be hosted in inorganic pores as well as in organic pores. Furthermore, the distribution of adsorbed moisture is mainly controlled by the VRo, component wettability (i.e., organic matter, clay, pyrite, and carbonate), and pore structure (micro-/mesopore distribution). In addition, a subtle adsorbed moisture may significantly reduce both the pore volume (PV) and specific surface area (SSA) of micropores, and the effect on micropores and SSA is more pronounced than that on the respective non-micropores and PVs. Additionally, the mechanism of clay swelling and pore expansion in clayey shale can provide certain insights for water–methane competitive adsorption, identifying clay type and pore size, and the formation of organo-mineral complexes.

In recent years, control of bistable flow of slit jet has attracted the interests of researchers due to its extensive applications in many fields. But there are still many problems in controlling jet flow by temperature. In order to further explore the influence of temperature on jet flow. This paper mainly carried out the numerical simulation on the control of bistable flow in a tube actuated by temperature. The slit jet was formed by two semi-circular tubes arranged side by side at different Re, different spacing ratios and different temperatures. It was found that, both spacing ratio and Re affect jet wall attachment. In case of temperature difference between the two semicircular tubes, the jet is inclined to the side at higher temperature. Higher temperature gradient corresponds to larger deflection angle and less arrival time of jet from the start point to the attached side. Setting the specific parameters, the split jet is stably attached to the side at higher temperature after running for a period of time. When the temperature of two walls is reversed, the split jet attached wall will also be conversed. This study lays a theoretical foundation for the further development of bistable characteristics of flow field and the application of dynamic thermal management devices.

Ethnopharmacological relevance: Hedyotis diffusa Willd. (H) and Scutellaria barbata D.Don (S) are ancient anti-cancer Chinese herb medicines. When combined, known as HS, it is one of the most commonly prescribed Chinese Medicines for cancer patients today in China. Aim of the study: The prevention of disease progression is a dominant concern for the growing number of men with prostate cancer. The purpose of this work is to evaluate the action and mode of action of Chinese Medicine recipe HS in inhibiting prostate cancer progression in preclinical models. Methods: Effects of HS were analyzed in prostate cancer cell lines by evaluating proliferation, cell cycle profile, DNA damage and key regulators responsible for G2 to M phase transition. The transcriptional activities of these regulators were determined by RT-PCR and ChIP. The efficacy of HS in vitro was validated in an animal model. Results: HS treatment was observed to reduce DNA content and accumulated prostate cancer cells at the G2/M phase. Immunolabeling for phospho-Histone H3 in association with nocodazole to capture mitotic cells confirmed that HS impeded G2 to M transition. After excluding DNA damage-induced G2 arrest, it was revealed that HS reduced expression of Cyclin B1, CDK1, PLK1 and Aurora A at both protein and mRNA levels, with concomitant reduction of H3K4 tri-methylation at their promoter-regions. Animals that received oral administration of HS with a dosage relevant to clinical application showed reduced tumor volume and weight with a reduction of Cyclin B1, CDK1, PLK1 and Aurora A protein levels. Conclusions: HS acts by impeding the G2 to M transition of prostate cancer cells. It is likely that the mode of action is transcriptionally suppressing proteins governing mitotic entry, without eliciting significant DNA damage.