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Direct analysis in real-time mass spectrometry (DART-MS) is an emerging in-situ ionization mass spectrometry analysis technology in recent years. DART is a non-contact surface desorption ionization technique, which is based on the principle of using helium or nitrogen as the working gas and generating excited high-energy particles by electric discharge. The excited state particles are accelerated by rapid heating and electric force, which instantly ionize the volatile compounds on the surface of the sample to be measured under atmospheric pressure, and then detected by mass spectrometry, thus achieving real-time direct analysis of the sample. DART-MS has the characteristics of simple sample preparation, quick and in-situ analysis. Since DART-MS was reported in 2005, it has become one of the most broadly used direct analysis methods and is extensively applied for the direct analysis of the quality, safety, origin and characteristics of food samples. Besides, it has been widely used in biomedicine, environmental monitoring, public safety, and drug analysis as well. Traditional Chinese medicines (TCMs) have been used for thousands of years in China, which gradually move towards to the world arena. The composition of TCM is very complicated, often containing many different chemical components of different types and properties, such as flavonoids, alkaloids, terpenoids, etc. Therefore, the analysis of the chemical basis of the efficacy and quality evaluation of TCMs are very crucial. In recent years, the development of DART-MS technology has provided many new opportunities for direct and rapid analysis of active ingredients in TCMs. The review was focused on the applications of DART-MS in TCMs, which covered the principle, characteristics, influencing factors and technological progress of DART-MS technology, and systematically summarized the research and application of this technology in TCMs, including qualitative and quantitative analysis. In addition, this review briefly introduced the progress of the application of DART-MS in combination with other techniques, such as thin-layer chromatography, imaging mass spectrometry and solid-phase microextraction in the profiling of TCMs, and provided further perspectives on its application development.

Uranium is one of the important strategic resources. It plays a decisive role in ensuring the stable development of nuclear energy. The shortage of uranium resources on land has aroused widespread concern. The total amount of uranium resources in seawater is more than 1 000 times that of land uranium resources. To ensure a stable supply of uranium, the research on the recovery of uranium from seawater has never stopped since the 1950s. The chelating functional adsorbent containing amidoxime group showed excellent adsorption ability and high selectivity for uranium over other co-existing metallic ions. In view of the important problems in the recovery of uranium, this paper reviewed the research progress in uranium desorption from the loaded uranium amidoxime materials. The desorption behavior, mechanism and characters of the loaded uranium materials with inorganic acidic solutions, alkaline solutions and organic complex solutions were summarized. The effect of co-existing metals on the uranium desorption was evaluated. Some problems were proposed to be investigated and solved further in the future. The possibility and feasibility for application of the advanced desorption technology in large-scale industrial desorption and recovery of uranium from the loaded chelating functional adsorbent containing amidoxime group were evaluated.

Objective To evaluate the protective effect and inflammation inhibition mechanism of icariin (ICA) on lung injury in rat model with severe acute pancreatitis (SAP). Methods The rats were randomly divided into sham operation group (sham group), model group (SAP group, 5% sodium taurocholate was retrograde pumped into bile duct according to 0.1 mL/kg through micropump) and experimental group (ICA group, icariin 80 mg/kg intervention was given 2 hours before modeling). There were 6 rats in each group. Twenty-four hours after the establishment of the model, the inferior vena cava blood, pancreatic tissue and lung tissue were collected. The pathological injury of pancreas and lung was observed by HE staining; The activity of amylase, serum IL-6, IL-1β and TNF-α were measured by ELISA; The expression of inflammatory factors IL-6, IL-1β and TNF-α in lung tissue was determined by immunohistochemical staining; And the ratio of phosphorylated JNK/JNK to phosphorylated NF-κB/NF-κB in lung tissue was measured by Western blot. Results The pathological scores of pancreas and lung in SAP group were significantly higher than those in sham group; And the pathological scores of pancreas and lung in ICA group were significantly lower than those in SAP group. Serum amylase activity, serum IL-6, IL-1β and TNF-α content and the expression of IL-6, IL-1β and TNF-α in lung tissue in SAP group were significantly higher than those in sham group; While serum amylase activity, serum IL-6, IL-1β and TNF-α content and the expression of IL-6, IL-1β and TNF-α in lung tissue in ICA group were significantly lower than those in SAP group. The level of phosphorylated JNK and phosphorylated NF-κB in lung tissue of SAP group were significantly higher than those of sham group; While icariin might significantly reduce the level of phosphorylated JNK and phosphorylated NF-κB in lung tissue. Conclusions ICA ameliorates lung injury in SAP rat model by inhibiting acute inflammation response,which is potentially mediated by JNK/NF-κB signal pathway.

Objective: In this study, the finite element simulation was integrated into random vibration experiment to provide a new way of thinking about transportation packaging. Methods: The red wine inner packaging spacer, made of three different cushioning materials, was used as the research object, and the vibration response was studied through random vibration experiment. Then the finite element simulation was used to analyze the correlation between the experiment and the simulation results. Results: The results of random vibration test were highly consistent with the results of finite element simulation, and the finite element simulation was less material-and time-consuming, compared with the random test. Conclusion: The combination of random experiment and finite element method can improve the efficiency of the experiment. The finite element simulation method can provide effective guidance for the analysis and design of product inner packaging under the vibration environment of transportation.

Numerical simulation can establish corresponding models for temperature field, molten pool shape, residential stress, microstructure evolution in the metal SLM process effectively. Meanwhile this model can accurately predict the performance of forming parts, and provide scientific basis for process parameters optimization, consequently boost the metal SLM to industry application. In this paper, the latest research progress of numerical simulation in the process of metal laser additive manufacturing was summarized, including temperature field, molten pool dynamics, residual stress and deformation in the forming part, and microstructure change.The latest progress of numerical simulation in metal SLM process was summarized, and the metal SLM process was analyzed. Finally, the future development trend was put forward that metal SLM process numerical simulation should be combined with big data, artificial intelligence, deep learning and other technologies and numerical simulation accuracy will be further improved,the processing window of metal laser additive manufacturing will be broadened,and guidance will be provided for the development of individual products.

'Mung Bean Rock' or 'Green Bean Rock' is a type of clay-like rock formed by Paleomatization and diagenesis. These rocks are distributed mainly between early and middle Triassic strata in Southwestern China and are good regionally isochronal mark beds. Studying the diagenetic age of 'Mung Bean Rock' is of great significance for further understanding of its diagenetic mechanism and age background. The debris zircon of 'Mung Bean Rock' in Chongqing Tongliang was used for U-Pb dating by LA-ICP-MS in this study. The zircon crystals have almost complete shape and zoning textures with high U and Th content, typical of magma zircon. Weighted average ages of the zircon 206Pb/238U peak at 245.86±0.98 Ma and 277.6±3.8 Ma. 'Mung Bean Rock' is located in the base of the Leikoupo Formation, the age of 245.86 Ma represents the timing of the zircons entering the sedimentary basin with volcanic ash at the base of the Leikoupo Formation in Tongliang, Chongqing. The age is similar to that of the tuff in Guizhou and Guangxi, indicating that regional volcanic eruption occurred at around 246 Ma. The older zircon was brought into the sedimentary basin during weathering of early igneous rocks and deposited with 'Mung Bean Rock'. A peak age at 277 Ma may imply that there was magmatic activity in the middle Permian period.

In order to reduce the pulsation of output angler velocity of the non-coaxial style of two-output impulse generating mechanism,by using rigid body dynamics software ADAMS for parametric modeling,and combining the MATLAB for data analysis,the variation law of the double output rod angular speed and acceleration and the institutional average,pulsation coefficient and abrupt change of angular acceleration with crank length change are obtained.Through the simulation analysis of example,the consistency of output motion and the crank speed adjustability are verified,and the variation law of the mechanism pulsation will be decrease with the increase of crank length.Finally,the impact of long-rod OE and EF change on the double output motion law of mechanism is analyzed,it is shows that,after increasing the length of the rod OE and EF,the mechanism pulsation decreased,a theoretical basis of the dimension synthesis and optimization of the impulse generating mechanism is provided.

The Dazhuyuan bauxite deposit is one of the most important deposits discovered during recent decades, and the Wuchuan-Zheng'an-Daozhen bauxite area (simplified as Wuzhengdao area) has also been listed as one the first uncompartmentalized prospecting areas on the national level. In order to promote prospecting, it is urgent to summarize the characteristics of the Dazhuyuan typical deposit and the regional ore-forming condition and outline the metallogenic regularity for the Wuzhengdao bauxite area. Based on the analysis of ore-bearing strata, structure, paleoclimatology, palaeogeomorphology and palaeogeography, the distribution of ore-bearing strata (the Dazhuyuan Formation, C2d), the existence of ore-source strata (Hanjiadian Formation, S1hj), the dissolution of limestone from the basement (the Huanglong Formation, C2h), and the stable stretching of syncline are identified as the most four most important key-points for the further prospecting of bauxite deposits in this area. The Liyuan-Luchi syncline, the Zhangjiayuan syncline, the Datang syncline, the Xinmo syncline, the Daozhen syncline, the Taoyuan syncline, the Anchang syncline and the Huanxi syncline have also been chosen as the main targets for uncompartmentalized prospecting and ore-genetic models for different kinds of bauxite deposits have been built, clearing the key exploration prospecting direction. Since 2012, three superlarge-scale, four large-scale and three middle-scale bauxite deposits have been discovered and about 470 million ton of bauxite have been confirmed, which show a remarkable result of uncompartmentalized prospecting in the Wuzhengdao area, North Guizhou. The regularity and ore-genetic model for bauxite deposits, based on practice, can provide scientific evidence for uncompartmentalized prospecting and further exploration in the Wuzhengdao area.

Equipment for breaking and blasting large barriers (EBBLB) is new break-blast equipment, which inevitably induces ground vibration and may cause substantial damage to rock mass and nearby structures as well as human beings. The ground vibration induced by break-blast is one of the inevitable outcomes. By monitoring vibration at measuring points at different distances from blasting center, time history curve of vibrating velocity can be obtained; it can be drawn that blasting seismic waves are generated mainly from the explosion of the precharge. Furthermore, different approaches have been adopted to fit relationship between particle peak velocity (PPV) and distance from blasting center, comparative analysis of which provides the most appropriate relation expression to predict attenuation of PPV of vibration with distance from blasting center. The relation between vibration frequency and distance from blasting center is obtained by Fourier transform. And the research decomposes vibrating signals in vertical direction of different distances from blasting center with Hilbert-Huang Transform (HHT), extracting information of empirical mode components of blasting vibration signals; thus vibrating signals are contracted by spectrum information and energy information, three-dimensional energy, and energy attenuation of vibration with different distances from blasting center. The study can predict ground vibration generated by EBBLB and assess its damaging effects of blasting vibration for security and protection.

Telencephalic organoids generated from human pluripotent stem cells (hPSCs) are a promising system for studying the distinct features of the developing human brain and the underlying causes of many neurological disorders. While organoid technology is steadily advancing, many challenges remain, including potential batch-to-batch and cell-line-to-cell-line variability, and structural inconsistency. Here, we demonstrate that a major contributor to cortical organoid quality is the way hPSCs are maintained prior to differentiation. Optimal results were achieved using particular fibroblast-feeder-supported hPSCs rather than feeder-independent cells, differences that were reflected in their transcriptomic states at the outset. Feeder-supported hPSCs displayed activation of diverse transforming growth factor β (TGFβ) superfamily signaling pathways and increased expression of genes connected to naive pluripotency. We further identified combinations of TGFβ-related growth factors that are necessary and together sufficient to impart broad telencephalic organoid competency to feeder-free hPSCs and enhance the formation of well-structured brain tissues suitable for disease modeling.