A self-powered vibration sensor for downhole drilling tools based on hybrid electromagnetic-triboelectric nanogenerator.

The vibration of downhole drilling tools is important to the drilling process, which needs to be measured in real time. Here, a self-powered vibration sensor for downhole drilling tools based on a hybrid electromagnetic-triboelectric nanogenerator is proposed in this research. The sensor has high reliability because the triboelectric nanogenerator (TENG) and the electromagnetic generator (EMG) parts of the sensor can be used as vibration sensors alone, and it may also supply power to other micro-power measurements while drilling instruments when the TENG and the EMG are used in parallel to increase the output power. Test results show that for the TENG part, the maximum output voltage, current, and power are 14 V, 5.2 µA, and 3.2 µW, respectively, with a 1 MΩ resistance in series, and for the EMG part, they are 1.22 V, 33 µA, and 21.8 mW, respectively, with a 10 Ω resistance in series. Further tests show that the measurement range of both the TENG and EMG is 0-11 Hz, the measurement error of both is less than ±5%, and both can work normally in the temperature range of less than 250 °C. In addition, this research also builds a wireless vibration data transmission system based on the sensor, which shows the potential for use in the wireless sensing field.

Tanshinone II A improves the chemosensitivity of breast cancer cells to doxorubicin by inhibiting ß-catenin nuclear translocation.

Numerous evidence link aberrant nuclear ß-catenin accumulation to the development of breast cancer resistance, therefore, targeted inhibition of ß-catenin nuclear translocation may effectively improve the chemosensitivity of breast cancer. Doxorubicin (Dox) is the most commonly used chemotherapeutic drug for breast cancer. Here, we determined that tanshinone II A (Tan II A) could improve the sensitivity of Dox-resistant breast cancer MCF-7/dox cells to Dox, and evaluated whether the sensitization effect of Tan II A on Dox was targeted to inhibit ß-catenin nuclear translocation. The results showed that Tan II A not only significantly inhibited the nuclear translocation of ß-catenin in MCF-7/dox cells treated by Dox but also inhibited the nuclear translocation of ß-catenin in MCF-7 cells treated by Dox to a certain degree. Furthermore, when the above two cells treated by Dox combined with Tan II A were intervened with ß-catenin agonist WAY-262611, with the re-nuclear translocation of ß-catenin in the cells, the sensitization effect of Tan II A on Dox was greatly reduced. These results indicated that Tan II A could improve the chemosensitivity of breast cancer cells to Dox by inhibiting ß-catenin nuclear translocation. Therefore, Tan II A could be used as a potential chemosensitizer in combination with Dox for breast cancer chemotherapy.

Development of self-powered bubble velocity sensor for gas-liquid two-phase flow based on triboelectric nanogenerator.

Bubble velocity of gas-liquid two-phase flow in coalbed methane well is an key parameter for formulating coalbed methane drainage technology. In this paper, a self-powered bubble velocity sensor (GLT-TENG) of two-phase flow, which is composed of distributed copper electrodes and low-density polyethylene wrapped in an outer layer, is proposed and analyzed based on triboelectric nanogenerator. Test results show that the measurement range is 0-0.49 m s-1 with a measurement error less than 6% when the GLT-TENG is used to measure a single bubble, but the measurement errors are inversely proportional to the time interval (the ratio of distance to speed difference) between the two bubbles when the GLT-TENG is used to measure continuous bubbles, and the measurement accuracy can reach 100% when the bubble time interval is greater than 0.3 s. The maximum output can be achieved when the bubble velocity impulse is 6200 cm3 · cm s-1, that is, the maximum output voltage and current are 0.38 V and 6.3 nA, respectively, and the maximum output power is 0.64 pW when the external load is 50 MΩ. In addition, the temperature and pulverized coal tests show that GLT-TENG has a good signal-to-noise ratio in the coalbed methane well environment, which can meet the actual working conditions.

Tanshinone IIA promotes cardiac differentiation and improves cell motility by modulating the Wnt/ß­catenin signaling pathway.

Although the cardiovascular pharmacological actions of Tanshinone IIA (TanIIA) have been extensively studied, research on its roles in cardiac regeneration is still insufficient. The present study employed the cardiac myoblast cell line H9c2 to evaluate the possible roles of TanIIA in cardiac regeneration. It was found that certain concentration of TanIIA inhibited cell proliferation by suppressing the expression of proteins related to the cell cycle [cyclin dependent kinase (CDK)4, CDK6 and cyclin D1] and proliferation [c­Myc, octamer­binding transcription factor 4 (Oct4) and proliferating cell nuclear antigen (PCNA)] without inducing apoptosis. In this process, the expression of cardiac troponin in the treated cells was significantly increased and the migration of the treated cells toward the wound area was significantly enhanced. Meanwhile, TanIIA inhibited the canonical signaling pathway through increasing the expression of glycogen synthase kinase 3ß (GSK­3ß) and adenomatous polyposis coli (APC) and increased the expression of Wnt11 and Wnt5a in the noncanonical Wnt signaling pathway. Following ß­catenin agonist WAY­262611 intervention, the effect of TanIIA on the promotion of cardiac differentiation and improved cell migration was significantly reduced. In conclusion, it was hypothesized that TanIIA could promote cardiac differentiation and improve cell motility by modulating the Wnt/ß­catenin signaling pathway. These results suggest that TanIIA may play beneficial roles in myocardial regeneration following stem cell transplantation.

Research on the Potential of Spherical Triboelectric Nanogenerator for Collecting Vibration Energy and Measuring Vibration.

The traditional downhole drilling vibration measurement methods which use cable or battery as power supplies increase the drilling costs and reduce the drilling efficiency. This paper proposes a spherical triboelectric nanogenerator, which shows the potential to collect the downhole vibration energy and measure the vibration frequency in a self-powered model. The power generation tests show that the output signal amplitude of the spherical triboelectric nanogenerator increases as the vibration frequency increases, and it can reach a maximum output voltage of 70 V, a maximum current of 3.3 × 10-5 A, and a maximum power of 10.9 × 10-9 W at 8 Hz when a 10-ohm resistor is connected. Therefore, if the power generation is stored for a certain period of time when numbers of the spherical triboelectric nanogenerators are connected in parallel, it may provide intermittent power for the low-power downhole measurement instruments. In addition, the sensing tests show that the measurement range is 0 to 8 Hz, the test error is less than 2%, the applicable working environment temperature is below 100 degrees Celsius, and the installation distance between the spherical triboelectric nanogenerator and the vibration source should be less than the critical value of 150 cm because the output signal amplitude is inversely proportional to the distance.

Development of gas-liquid two-phase flow pattern sensor of coalbed methane based on the principle of triboelectric nanogenerator.

During the mining of coalbed methane (CBM), real-time measurement conducted by a gas-liquid two-phase flow pattern sensor is one of the key steps in the development of a reasonable discharge and mining system. In this study, a self-powered flow pattern sensor based on the triboelectric nanogenerator (TENG) was proposed and analyzed. The basic principle is as follows: when the sensor is impacted by the bubbles of the two-phase flow, triboelectric charges are generated due to the contact between the copper electrode, which plays the dual roles of electrode and positive triboelectric material, and the PTFE which acts as negative triboelectric material. This is transferred to produce voltage signals, thus realizing the measurement of the bubbles. On this basis, the characteristics and duration of the bubbles were further analyzed to measure the two-phase flow pattern. In addition, relevant characteristic parameters of the sensor were determined through analysis and experiment; when the product of the volume and velocity of the bubbles is greater than [Formula: see text] and the impact frequency is less than 0.45 Hz, the sensor can be used normally. We also explored the possibility of using the sensor to collect the impact energy of the bubbles to be used by other devices. As indicated by subsequent experiments on the sensor, it performs in a stable manner and can be used to measure the gas-liquid two-phase flow pattern, showing broad application prospects in the field of CBM.

Self-Powered Speed Sensor for Turbodrills Based on Triboelectric Nanogenerator.

Turbodrills play an important role in underground energy mining. The downhole rotational speed of turbodrills is one of the key parameters for controlling the drilling technology. Therefore, it is necessary to measure the rotational speed of the turbodrills in real time. However, there is no dedicated speed sensor for the working environment of turbodrills at present. Therefore, based on the working principle of triboelectric nanogenerator (TENG), a self-powered speed sensor which can measure the speed of the turbodrills is proposed in this study. Besides, since the sensor is self-powered, it can operate without power supply. According to the laboratory test results, the measurement error of the sensor is less than 5%. In addition, the self-powered performance of the sensor was also explored in this study. The test shows that the maximum generating voltage of the sensor is about 27 V, the maximum current is about 7 µA, the maximum power is about 2 × 10-4 W, and the generated electricity can supply power for ten LED (light-emitting diode), which not only meets the power supply requirements of the sensor itself, but also makes it possible to further power other underground instruments.

Combination of tanshinone IIA and doxorubicin possesses synergism and attenuation effects on doxorubicin in the treatment of breast cancer.

Doxorubicin (Dox) is a first-line drug for breast cancer chemotherapy. However, with the prolongation of chemotherapy cycle, breast cancer cells are increasingly tempt to resist Dox, and meanwhile, high cumulative dose of Dox brings enhancing toxic side effects, and these effects may lead to chemotherapy failure. Hence, it is necessary to search an agent in combination medication with Dox, which can not only enhance the chemosensitivity of Dox but also reduce the toxic side effects. Tanshinone IIA (Tan IIA) is reported to have antitumor activity in addition to its cardiovascular protective effects. We employed human breast cancer MCF-7 and MCF-7/dox cells in order to assess whether Tan IIA might perform such function. Our in vitro studies showed that Tan IIA could enhance the sensitivity of breast cancer cells to Dox through inhibiting the PTEN/AKT pathway and downregulating the expression of efflux ABC transporters including P-gp, BCRP, and MRP1. In addition, our in vivo studies showed Tan IIA enhanced the chemotherapeutic effect of Dox against breast cancer while reducing its toxic side effects including weight loss, myelosuppression, cardiotoxicity, and nephrotoxicity. Therefore, Tan IIA could be used as a novel agent combined with Dox in breast cancer therapy.