The Computer Simulation of the Interaction Between Roller Bit and Rock Dekun Ma; Dekun Ma Southwest Petroleum Institute, P.R. China Search for other works by this author on: This Site Google Scholar Desheng Zhou; Desheng Zhou Southwest Petroleum Institute, P.R. China Search for other works by this author on: This Site Google Scholar Rong Deng Rong Deng Southwest Petroleum Institute, P.R. China Search for other works by this author on: This Site Google Scholar Paper presented at the International Meeting on Petroleum Engineering, Beijing, China, November 1995. Paper Number: SPE-29922-MS https://doi.org/10.2118/29922-MS Published: November 14 1995 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Ma, Dekun, Zhou, Desheng, and Rong Deng. "The Computer Simulation of the Interaction Between Roller Bit and Rock." Paper presented at the International Meeting on Petroleum Engineering, Beijing, China, November 1995. doi: https://doi.org/10.2118/29922-MS Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentAll ProceedingsSociety of Petroleum Engineers (SPE)SPE International Oil and Gas Conference and Exhibition in China Search Advanced Search AbstractIn this paper, the surface of each tooth of roller bits is represented by scores of points, whose 3-D compound coordinates are used to reflect the shape and size of the tooth. Thus, the cutting structure of the bit together with their movement is represented by the time-sequence of the coordinates of the several thousand points. Hence, the computer simulates the roller bit.In the simulation, the bottom hole that changes with drilling is represented, according to the sequence of time, as a series of time points. And the bottom hole at each time point is represented, according to space, as tens of thousands of points, whose 3-D compound coordinates are used to express the shape and size of the bottom hole at an arbitrary time. The changes of the bottom hole with drilling are described by a recurrence model made up of the bottom hole at each time point. Hence the reproduction of the bottom hole is on computer.The well bore is dealt with the same principle as the bottom hole.The interaction between the roller bit and the rock is represented by the balance model of the vertical and the lateral interactions.The index, inclination, the shape and size of rock fragile breakage by a contacting tooth at any time are calculated by the fragile criterion model and the rock breakage model. The craters with various shapes are formed by the rock fragile breakage and the amount of the rock occupied by the tooth directly.BRIAS, the simulation software thus set up, can be used to analyse all the interactions in the process of drilling. Detailed experiment data have proved that the simulation software is able to well reflect the effects of the subtle differences of bit structure, WOB and rock properties upon the rotation rate and the torque of the bit.IntroductionThe content of the interaction between a roller bit and bottom rock is very extensive. This paper mainly deals with two major issues: how the bottom rock is smashed upon the force of the bit; How the roller bit moves under the action of the drilling string and the reaction of the bottom rock. The key problem here is the relative movement and the interaction between the tooth and the bottom hole. In fact, the movement of the bit can be analysed if the pressures upon the bit are available; the smashing of the rock can be studied if the pressures upon the rock are clear.P. 309 Keywords: bit selection, roller bit, drilling, tooth, interaction, computer simulation, teeth, bit structure, fragile breakage, society of petroleum engineers Subjects: Drill Bits This content is only available via PDF. 1995. Society of Petroleum Engineers You can access this article if you purchase or spend a download.
In this study, hollow olive-shaped BiVO4 and n−p core−shell BiVO4@Bi2O3 microspheres were synthesized by a novel sodium bis(2-ethylhexyl)sulfosuccinate (AOT)-assisted mixed solvothermal route and a thermal solution of NaOH etching process under hydrothermal conditions for the first time, respectively. The as-obtained products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy, Brunauer−Emmett−Teller surface area, and UV−vis diffuse-reflectance spectroscopy in detail. The influence of AOT and solvent ratios on the final products was studied. On the basis of SEM observations and XRD analyses of the samples synthesized at different reaction stages, the formation mechanism of hollow olive-shaped BiVO4 microspheres was proposed. The photocatalytic activities of hollow olive-shaped BiVO4 and core−shell BiVO4@Bi2O3 microspheres were evaluated on the degradation of rhodamine B under visible-light irradiation (λ > 400 nm). The results indicated that core−shell BiVO4@Bi2O3 exhibited much higher photocatalytic activities than pure olive-shaped BiVO4. The mechanism of enhanced photocatalytic activity of core−shell BiVO4@Bi2O3 microspheres was discussed on the basis of the calculated energy band positions as well. The present study provides a new strategy to enhancing the photocatalytic activity of visible-light-responsive Bi-based photocatalysts by p−n heterojunction.
Hexagonal V0.13Mo0.87O2.935 nanowires were hydrothermally synthesized at 220 °C for the first time. X-ray diffraction and field-emission scanning electron microscopy were utilized to characterize the phase and morphology of the nanowires, respectively. Transmission electron microscopy and selected area electron diffraction indicate that the nanowires are single crystalline, growing along the [001] direction. Interestingly, the nanowires easily become amorphous under the electron irradiation. The comparative hydrothermal experiments show that the molar ratio between the starting reagents of Mo and NH4VO3 plays a vital role in the anisotropic growth of nanowires. The photoluminescence measurement demonstrates that these nanowires exhibit two strong emission peaks at 420 and 438 nm, which are probably related to the intrinsic oxygen vacancies.
Developing multifunctional near-infrared (NIR) light-driven photothermal agents is in high demand for efficient cancer therapy. Herein, PEGylated Cu3BiS3 hollow nanospheres (HNSs) with an average diameter of 80 nm were synthesized through a facile ethylene glycol-mediated solvothermal route. The obtained PEGylated Cu3BiS3 HNSs exhibited strong NIR optical absorption with a large molar extinction coefficient of 4.1 × 10(9) cm(-1) M(-1) at 980 nm. Under the irradiation of a 980 nm laser with a safe power density of 0.72 W cm(-2), Cu3BiS3 HNSs produced significant photothermal heating with a photothermal transduction efficiency of 27.5%. The Cu3BiS3 HNSs also showed a good antitumoral drug doxorubicin (DOX) loading capacity and pH- and NIR-responsive DOX release behaviors. At a low dosage of 10 μg mL(-1), HeLa cells could be efficiently killed through a synergistic effect of chemo- and photothermo-therapy respectively based on the DOX release and the photothermal effect of Cu3BiS3 HNSs. In addition, Cu3BiS3 HNSs displayed a good X-ray computed tomography (CT) imaging capability. Furthermore, Cu3BiS3 HNSs could be used for efficient in vivo photothermochemotherapy and X-ray CT imaging of mice bearing melanoma skin cancer. This multifunctional theranostic nanomaterial shows potential promise for cancer therapy.
Abstract Mechanochromic photonic crystals are attractive due to their force-dependent structural colors; however, showing unrecordable color and unsatisfied performances, which significantly limits their development and expansion toward advanced applications. Here, a thermal-responsive mechanochromic photonic crystal with a multicolor recordability-erasability was fabricated by combining non-close-packing mechanochromic photonic crystals and phase-change materials. Multicolor recordability is realized by pressing thermal-responsive mechanochromic photonic crystals to obtain target colors over the phase-change temperature followed by fixing the target colors and deformed configuration at room temperature. The stable recorded color can be erased and reconfigured by simply heating and similar color-recording procedures respectively due to the thermoswitchable on-off mechanochromism of thermal-responsive mechanochromic photonic crystals along with solid-gel phase transition. These thermal-responsive mechanochromic photonic crystals are ideal rewritable papers for ink-freely achieving multicolor patterns with high resolution, difficult for conventional photonic papers. This work offers a perspective for designing color-recordable/erasable and other stimulus-switchable materials with advanced applications.
A new coding-decoding system was established through combining the line coding of near-infrared photonic crystals (NIRPCs) with diverse reflection wavelengths and their spatial reflection spectra (SRS).
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