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For actual demand of nearly horizontal hole drilling of coal seam methane, the paper proposed a scheme of auto-orientation of jet stream of hydraulic correction combining with hydraulic correction technology and designed a correction system based on the scheme. The correction system takes a single-chip microcomputer as control core, uses a pressure sensor to monitor changes of drilling hydraulic pressure so as to start or end hydraulic correction process, and adopts an angle sensor and a digital compass to detect azimuth and inclination of horizontal hole. Then the single-chip microcomputer determines jet direction in accordance with values of the inclination and azimuth and their correlations. The debugging indoor demonstrated feasibility of the scheme.

The patent data of rubidium and cesium separation based on IncoPat patent database was searched, and 2 617 patents related to rubidium and cesium separation were retrieved. The pattern of rubidium and cesium separation patents in terms of patent trends, technical status, geographical distribution and applicant status using the common visual chart analysis method were analyzed. Analysis shows that patents in the field of rubidium and cesium separation developed rapidly and were highly active from 2013 to 2021; current technological research and development hotspots of rubidium and cesium separation were B01J, G21F and C22B technical field; China and Japan were the main patent layout of rubidium and cesium separation worldwide; Beijing, Jiangxi, Shaanxi, Qinghai and other provinces and cities were mainly involved in rubidium and cesium separation patents in China; rubidium and cesium separation had high recognition and attention in manufactures of chemical materials; the main research institutions of rubidium and cesium separation technology were mainly distributed in China; the overall value of patents owned by the top 10 patent applicants were high; according to the current development trend for rubidium and cesium separation technology, there was still a lot of room for advancement in the field in the future, and Chinese patent applicants for rubidium and cesium separation could create effective and consistent development plans based on their own advantages and opportunities for advancement globally. [ABSTRACT FROM AUTHOR]

Aim: To investigate the photodynamic effect of CdSe/ZnS quantum dots (QDs) on pancreatic cancer cells and elucidate the probable mechanisms., Methods: The pancreatic cancer cell line SW1990 was treated with different concentrations of CdSe/ZnS QDs (0, 0.5, 1.0, 1.5, 2.0, 2.5 μmol/L), with or without illumination. The viability of SW1990 cells was tested using the Cell Counting Kit-8 (CCK-8) assay. The ultrastructural changes of SW1990 cells were observed by transmission electron microscopy. Apoptosis was detected by nuclear staining and flow cytometry (FCM). Reactive oxygen species (ROS) were measured by dichlorofluorescein diacetate via fluorescence microscopy. Expression of Bax, Bcl-2 and caspase-3 was measured by real-time polymerase chain reaction (PCR) and protein immunoblotting 24 h after SW1990 cells were treated with CdSe/ZnS QDs and illuminated., Results: The CCK-8 assay results showed that both CdSe/ZnS QDs with and without illumination suppressed SW1990 cell proliferation. Cell viability was significantly lower when illuminated or with a longer incubation time and a higher light dose. CdSe/ZnS QDs with illumination caused ultrastructural changes in SW1990 cells, such as organelle degeneration and chromatin condensation and aggregation at the periphery of the nucleus. Fluorescence microscopy and FCM showed that CdSe/ZnS QDs (1.5 μmol/L) with illumination increased SW1990 cell apoptosis (53.2%) and ROS generation compared with no illumination. Real-time PCR showed that expression of Bax and caspase-3 was upregulated and Bcl-2 was downregulated. Immunoblotting results were consistent with real-time PCR results. Inhibition of ROS and apoptosis both attenuated QD-photodynamic-therapy-induced cell death., Conclusion: CdSe/ZnS QDs can be used as a photosensitizer to inhibit SW1990 cell proliferation through ROS generation and apoptotic protein expression regulation.