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In recent years, the coagulation properties of inorganic minerals such as kaolin and zeolite have been demonstrated. This study aimed to assess the hemostatic properties of three local clays from China: natural kaolin from Hainan, natural halloysite from Yunnan, and zeolite synthesized by our group. The physical and chemical properties, blood coagulation performance, and cell biocompatibility of the three materials were tested. The studied materials were characterized by using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). All three clays showed different morphologies and particle size, and exhibited negative potentials between pH 6 and 8. The TGA and DSC curves for kaolin and halloysite were highly similar. Kaolin showed the highest water absorption capacity (approximately 93.8% ± 0.8%). All three clays were noncytotoxic toward L929 mouse fibroblasts. Kaolin and halloysite showed blood coagulation effects similar to that exhibited by zeolite, indicating that kaolin and halloysite are promising alternative hemostatic materials. [ABSTRACT FROM AUTHOR]

The sintered permeable brick was prepared using granite waste and burnt coal cinder (BCC) as raw materials to ensure the utmost utilization of both solid wastes. The effect of various parameters, such as the proportion of raw materials, granite particle size and sintering temperatures on the properties of the permeable brick were studied, and the relevant sintering mechanism was clarified. The differential scanning calorimetry curves indicate that the mixture of granite waste and BCC begins to melt at a lower temperature, which is lower than the temperature for melting them alone, so the use of them to prepare sintered bricks will reduce energy consumption. The optimal conditions for the preparation of the permeable bricks were determined as the mass ratio of granite waste to BCC of 80: 20, sintering temperature of 1150–1175°C, and granite particle size of.9–1.25 mm. It was found that the permeability and the flexural strength of the samples can reach 3.41 × 10 −2 cm/s and 4.2 MPa, respectively, which both exceed the requirements specified in the national standard of China. [ABSTRACT FROM AUTHOR]

The Dabei deep high-pressure condensate gas field occupies the paramount position in the Tarim Oilfield in China, the exploration and developments of which have been progressing. Since the initial development, the wax deposition and plugging in the wellbore and gathering pipeline have been the most bothering issues, resulting in the reduction or even shutdown of condensate gas well production. Therefore, the wax appearance temperature of Dabei condensate oil was studied using the capillary viscometer, differential scanning calorimetry (DSC), and polarizing microscope observation. The wax content was tested by using the DSC and crystallization separation test method. Finally, the wax appearance temperatures of degassed condensate oil and equilibrium condensate oil under different pressures were tested. Experimental results show that the wax appearance temperature measured by polarizing microscope observation was higher than that measured by the DSC and capillary viscometer, the lag of which can be recorded as the cloud point. The wax appearance temperature measured by polarizing microscope observation is of high accuracy. Secondly, the DSC method is not sufficient for measuring wax precipitation at low temperatures, showing a lower wax content than the crystallization separation test method. Thus, the wax content of Dabei condensate oil can be better measured by using the crystallization separation test method. Additionally, the wax precipitation law of equilibrium condensate oil is opposite to that of degassed condensate oil. The wax appearance temperature of equilibrium condensate oil increases as the pressure decreases. The results of wax appearance temperature of equilibrium condensate oil provide a useful and quick index to judge the potential risk of wax precipitation in the Tarim Oilfield, which can provide an efficient strategy for the development of waxy condensate gas reservoirs and the optimization of wax prevention and treatment technology. [ABSTRACT FROM AUTHOR]

We developed a novel preparative method for nanoparticle albumin-bound (nab) paclitaxel with high drug loading, which was based on improved paclitaxel solubility in polyethylene glycol (PEG) and self-assembly of paclitaxel in PEG with albumin powders into nanoparticles. That is, paclitaxel and PEG were firstly dissolved in ethanol, which was subsequently evaporated under vacuum. The obtained liquid was then mixed with human serum albumin powders. Thereafter, the mixtures were added into phosphate-buffered saline and nab paclitaxel suspensions emerged after ultrasound. Nab paclitaxel was finally acquired after dialysis and freeze drying. The drug loading of about 15% (W/V) were realized in self-made nab paclitaxel, which was increased by approximately 50% compared to 10% (W/V) in Abraxane. Now this new preparative method has been authorized to obtain patent from China and Japan. The similar characteristics of self-made nab paclitaxel compared to Abraxane were observed in morphology, encapsulation efficiency, in vitro release, X-ray diffraction analysis, differential scanning calorimetry analysis, and circular dichroism spectra analysis. Consistent concentration-time curves in rats, biodistributions in mice, anti-tumor activities in mice, and histological transmutation in mice were also found between Abraxane and self-made nanoparticles. In a word, our novel preparative method for nab paclitaxel can significantly improve drug loading, obviously decrease product cost, and is considered to have potent practical value. [ABSTRACT FROM AUTHOR]

Based on the background that a large amount of iron tailings was stockpiled in China, the most appropriate preparation conditions of producing autoclaved aerated concrete (AAC) with iron tailing was studied. The slurry properties were tested to evaluate the effects of the raw material factors on gas forming character. The compressive and specific strengths were measured to assess the feasibility of producing B05, A2.5 AAC blocks. The analysis of morphology, mineral components and thermal property were carried out in order to determine the mineral composition of iron tailing AAC blocks. Leaching toxicity was determined to ensure the environmental safety of iron tailing AAC blocks. The results shows that under the following conditions, cement 8%, quicklime 21%–27%, 20 min ball milled siliceous 62%–68% (with 40%–60% substituted by iron tailings), gypsum 3%, ratio of water to raw material (W/R) 0.6, aluminum (Al) powder 0.14% and at 1.4 MPa steam pressure maintaining for 8 h, the bulk density can be between 490 and 525 kg/m 3 , compressive strength higher than 2.5 MPa and specific strength higher than 4700 N m/kg. The main minerals in the AAC were dough-like CSH gel, flake-like tobermorite and long-strip anhydrate besides quartz and other residual minerals from the iron tailings. The compressive strength is mainly attributed to the interconnected microstructure constituted of CSH gel and tobermorite. The thermal analysis also proved the existing of the main minerals. [ABSTRACT FROM AUTHOR]

The disposal of medical waste has become an increasing environmental issue since the COVID-19 epidemic outbreaks. Conventional disposal methods have produced waste of fossil resources and environmental problems. In this study, the waste medical mask-derived materials were tested as viscosity reducer and pour point depressant to evaluate the possibility of being used as crude oil fluidity improver. The results show that the materials derived from the three parts of the waste medical mask can reduce the viscosity and pour point of each crude oil samples from different oilfields in China. The middle layer of the medical mask (PP-2) displays the highest efficiency, and the viscosity reduction rate and maximum pour point reduction reaches 81% and 8.3 °C at 500 ppm, respectively. A probable mechanism of improving rheological properties of the crude oil samples by the medical mask-derived materials was further proposed after the differential scanning calorimetry (DSC) analysis and the wax crystal morphology analysis. We hope this work could provide a way to solve the current environmental issues under COVID-19. [Display omitted] • Waste medical mask can improve the fluidity of crude oil samples from different oilfields in China. • The middle layer of the medical mask (PP-2) at 500 ppm exhibits the highest effeciency with a viscosity reduction rate of 81%, and the maximum pour point reduction is 8.3 °C. • Differential scanning calorimetry (DSC) and paraffin crystal morphology characterization were conducted to support the possible mechanism. • This work provides a way to solve the current environmental problems caused by COVID-19. [ABSTRACT FROM AUTHOR]

To achieve carbon neutrality and optimize China's energy structure, pyrolysis (thermal cracking) was selected to recycle the Waste Fischer-Tropsch wax (WFTW) produced in large quantities from Fischer-Tropsch synthesis plants, which has rich hydrocarbon content and high calorific value. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), thermogravimetry-mass spectrometry (TG-MS), and thermogravimetric-infrared spectroscopy (TG-IR) were used to investigate the pyrolysis characteristics and mechanism of WFTW. The TG and DSC showed that the main pyrolysis temperature range of WFTW was 230–480 °C, and the heating rate affected the temperature range greatly. Theoretically, more than 87% of the calorific value in the WFTW can be recovered as liquid fuels, and the most suitable heating rate was 15 °C/min. TG-MS and TG-IR showed pyrolysis products at different stages to further investigate the pyrolysis process and provide a basis for recycling WFTW. The activation energy calculated by Kissinger method is 215 ± 3 kJ/mol, and the mean apparent activation energy calculated by Starink method is 133 ± 14 kJ/mol, showing a good agreement with Kissinger method at a high conversion rate (70–80%). • The pyrolysis characteristics and mechanism of waste Fischer-Tropsch wax were studied through TGA, DSC, TG-MS, and TG-IR. • Oligomerization, volatilization, and thermal cracking are important in the WFTW pyrolysis process. • The pyrolysis activation energy calculated by Starink method agreed with Kissinger method well at high conversion rates. • More than 87% of the energy content can be recovered as liquid fuel theoretically. [ABSTRACT FROM AUTHOR]

Bamboo processing is faced with increasing requirements of resource reusability in China. A large amount of waste bamboo green produced in bamboo processing needs to be recycled. Waste bamboo green contains a large number of environmentally friendly wax components. In this study, supercritical CO 2 extraction was used to extract bamboo green waste to obtain natural wax. Response surface methodology (RSM) was used to optimize the extraction process and the yield of bamboo green wax under pressure of 20–30 MPa, temperature of 318–328 K, and time of 30–90 min. The extracted bamboo green wax was characterized by gas chromatography and mass spectrometry (GC-MS). RSM optimization shows that under the conditions of 26 MPa, 328 K, and 56 min, the yield of bamboo green wax was the highest at 2.327%. The compositions of esters, fatty acids, sterols and so on in bamboo green wax were characterized by GC-MS. Differential scanning calorimetry (DSC) shows that the melting point of bamboo green wax is 334 K. At last, the economic evaluation of bamboo green wax was made to analyze its potential application prospect. It is supposed that bamboo green waste is a resource for natural wax with potential application value. [ABSTRACT FROM AUTHOR]

Damage to concrete structures with gypsum-contaminated aggregate occurs frequently. Aggregates in much of the southern part of China are contaminated with gypsum. Therefore, in this study, the effects of using different quantities of gypsum-contaminated aggregate on the expansion and compressive strength of concrete were investigated over a period of one year. Two groups of concrete were designed with the gypsum-contaminated aggregate containing different parts of fine and coarse aggregate, respectively. The SO3 contents were 0%, 0.5%, 1%, 1.5%, 3%, 5%, and 7% by weight of aggregate. X-ray diffraction (XRD), thermogravimetry (TG), and differential scanning calorimetry (DSC) were used to analyze the change in mineral composition over time. The microstructure was also studied by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The results showed that significant expansion and great loss in compressive strength did not occur in concrete if the content of SO3 lay below 1.5% and 3% in fine and coarse aggregates, respectively. The concentration of sulfate ions in concrete was not enough to form new a phase of gypsum. During the process of internal sulfate attack, the content of gypsum decreased and the content of ettringite increased. Ettringite was the main reason for the expansion damage of concrete. Additionally, the fracture mode of internal sulfate attack on concrete was the crack extension from gypsum to paste; finally, the aggregate separated from the paste. [ABSTRACT FROM AUTHOR]

Biochar amendment may alter the quantity and stability of soil organic matter (SOM), whichcould be quantified using thermogravimetry (TG) and differential scanning calorimetry(DSC) techniques. The present study was to evaluate the thermal stability of SOM after 8-yrconsecutive biochar application in the North China. The experiment consisted of fourtreatments: control (CK), biochar rate at 4.5 t ha−1 yr−1 (B4.5), biochar rate at 9.0 t ha−1yr−1 (B9.0), and crop straw return (SR). Soil samples were collected from the 0-10 cm layer.The results showed that the derivatives of thermogravimetry curves (DTG) andDSC curves had three peaks, near 100, 400 and 500˚ C for both the bulk soils. Thepercentage of thermal labile SOM (weight loss in 200–400˚ C accounting for that in200–550˚ C, %Exo1) followed the order of SR > CK > B4.5 > B9.0. Across thetreatments, the TG-T50(the temperature leading to half of SOM loss) showed the trendof B9.0 > B4.5 > CK > SR. Moreover, a negative correlation between %Exo1and TG-T50 existed (r= -0.975; P <0.05). The energy densities (ED) of SOM(energy release per unit SOM) followed the order of B9.0 > B4.5 > SR > CK.We concluded that biochar amendment increased the thermal stability of SOM. [ABSTRACT FROM AUTHOR]