Ensuring rib stability during pillar extraction is of prime importance in bord and pillar(B&P) method of underground coal mining with caving. Rib stability has been assessed here by way of assessing factor of safe...Ensuring rib stability during pillar extraction is of prime importance in bord and pillar(B&P) method of underground coal mining with caving. Rib stability has been assessed here by way of assessing factor of safety(FOS), a ratio of the strength of rib to stress on it. Earlier formulations for rib stability when applied to case studies gave very low FOS value suggesting significant ground control problems, which were contrary to the field observations. This has necessitated the need to revisit the concept of rib stability. The stress coming on the rib is estimated with the use of numerical modeling technique using the FLAC^(3D) software. The methodology of assessing rib-stability with the help of suggested rib-strength formulation has been validated at eight Indian coal mines. The outcome of this study finds relevance and importance in ensuring underground coal liquidation with improved safety and conservation.展开更多
The emerging development of Extractive Reference Substance (ERS) is a methodology that meets the needs for quality control for Chinese Herbal Medicines (CHM) and respects the holistic viewpoint of Traditional Chinese ...The emerging development of Extractive Reference Substance (ERS) is a methodology that meets the needs for quality control for Chinese Herbal Medicines (CHM) and respects the holistic viewpoint of Traditional Chinese Medicine (TCM) and its clinical use of multiple ingredients with synergistic effects. The convention of using just a selected few Chemical Reference Substances (CRS) cannot adequately assess the quality of intact CHM. A validated chemical spectrum of an ERS provides the global characteristics in order to more specifically identify and assess targeted CHM. This paper describes the fundamental concepts, potential significance, and basic criteria of ERS, along with methods of preparation and calibration. Given the diversity of CHM, the various problems that will occur in establishing the proper process of ERS will need to be solved in a step by step manner. The ERSs of Ziziphi spinosae semen and ERS of Fritillaria thunbergii bulbus are given as examples of the development of ERS and demonstrate why we are optimistic about the utility of this approach.展开更多
The purpose of the study was to evaluate the efficiency of the microwave (MW) extraction method by comparing it with a conventional method through evaluation of antimicrobial and synergism/antagonism activity of each ...The purpose of the study was to evaluate the efficiency of the microwave (MW) extraction method by comparing it with a conventional method through evaluation of antimicrobial and synergism/antagonism activity of each aquatic and ethanolic extracts samples, which were extracted from the dried plants (<em>Ficus sycomorus</em> leaves, <em>Lawsonia inermis</em> leaves and <em>Glycerrhiza glabra</em> Linn.). Nine samples of each plant for both solvents were irradiated with MW at several power outputs (180 w, 360 w, and 540 w) in several interval times (1, 2 and 3 minutes). The antibacterial activities of extracts and the synergistic effect between plants and antibiotics were evaluated using disk diffusion method against clinical isolated <em>Staphylococcus aureus</em> and <em>Escherichia coli</em>. The result revealed that the inhibition zone for more than 50% using aquatic and ethanolic samples results (extracted in two minutes and MW power 180 w) had shown the optimum extract and better antibiotic activity for each plant. Also, the results of ethanolic extracts used against selected microorganisms showed antimicrobial and synergistic effect with most antibiotics better than aquatic extracts. Our results indicate the possibility of using MW apparatus as an extractor to obtain bioactive compounds from plants and thus used in the treatment of bacterial infections, and some results of this study were encouraging. However, the antagonistic reactions of some extracts with some antibiotics and their use in combination should be further studied for<em> in vitro</em> activities. It is clearly a need to be furthermore evaluated, to identify the effective components, the mode of action and the possible toxic effect <em>in-vivo</em> of these ingredients.展开更多
The purpose of this paper is to determine the optimal size and number of tubes for a generic attenuator that is similar to Pelamis P2, the wave energy converter. Simulations using ANSYS Workbench, Design Modeler, and ...The purpose of this paper is to determine the optimal size and number of tubes for a generic attenuator that is similar to Pelamis P2, the wave energy converter. Simulations using ANSYS Workbench, Design Modeler, and AQWA are performed to study the energy absorption at the nodes between the tubes. The analysis is limited to linearized hydrodynamic fluid waves loading on floating bodies by employing three-dimensional radiation/diffraction theory in regular waves in the frequency domain. Three sets of tests are conducted by varying total tube number, each tube length and the order of tubes with different lengths. After a systematic study in the frequency domain, the optimal size and number of the genetic attenuator is recommended.展开更多
文摘Ensuring rib stability during pillar extraction is of prime importance in bord and pillar(B&P) method of underground coal mining with caving. Rib stability has been assessed here by way of assessing factor of safety(FOS), a ratio of the strength of rib to stress on it. Earlier formulations for rib stability when applied to case studies gave very low FOS value suggesting significant ground control problems, which were contrary to the field observations. This has necessitated the need to revisit the concept of rib stability. The stress coming on the rib is estimated with the use of numerical modeling technique using the FLAC^(3D) software. The methodology of assessing rib-stability with the help of suggested rib-strength formulation has been validated at eight Indian coal mines. The outcome of this study finds relevance and importance in ensuring underground coal liquidation with improved safety and conservation.
文摘The emerging development of Extractive Reference Substance (ERS) is a methodology that meets the needs for quality control for Chinese Herbal Medicines (CHM) and respects the holistic viewpoint of Traditional Chinese Medicine (TCM) and its clinical use of multiple ingredients with synergistic effects. The convention of using just a selected few Chemical Reference Substances (CRS) cannot adequately assess the quality of intact CHM. A validated chemical spectrum of an ERS provides the global characteristics in order to more specifically identify and assess targeted CHM. This paper describes the fundamental concepts, potential significance, and basic criteria of ERS, along with methods of preparation and calibration. Given the diversity of CHM, the various problems that will occur in establishing the proper process of ERS will need to be solved in a step by step manner. The ERSs of Ziziphi spinosae semen and ERS of Fritillaria thunbergii bulbus are given as examples of the development of ERS and demonstrate why we are optimistic about the utility of this approach.
文摘The purpose of the study was to evaluate the efficiency of the microwave (MW) extraction method by comparing it with a conventional method through evaluation of antimicrobial and synergism/antagonism activity of each aquatic and ethanolic extracts samples, which were extracted from the dried plants (<em>Ficus sycomorus</em> leaves, <em>Lawsonia inermis</em> leaves and <em>Glycerrhiza glabra</em> Linn.). Nine samples of each plant for both solvents were irradiated with MW at several power outputs (180 w, 360 w, and 540 w) in several interval times (1, 2 and 3 minutes). The antibacterial activities of extracts and the synergistic effect between plants and antibiotics were evaluated using disk diffusion method against clinical isolated <em>Staphylococcus aureus</em> and <em>Escherichia coli</em>. The result revealed that the inhibition zone for more than 50% using aquatic and ethanolic samples results (extracted in two minutes and MW power 180 w) had shown the optimum extract and better antibiotic activity for each plant. Also, the results of ethanolic extracts used against selected microorganisms showed antimicrobial and synergistic effect with most antibiotics better than aquatic extracts. Our results indicate the possibility of using MW apparatus as an extractor to obtain bioactive compounds from plants and thus used in the treatment of bacterial infections, and some results of this study were encouraging. However, the antagonistic reactions of some extracts with some antibiotics and their use in combination should be further studied for<em> in vitro</em> activities. It is clearly a need to be furthermore evaluated, to identify the effective components, the mode of action and the possible toxic effect <em>in-vivo</em> of these ingredients.
文摘The purpose of this paper is to determine the optimal size and number of tubes for a generic attenuator that is similar to Pelamis P2, the wave energy converter. Simulations using ANSYS Workbench, Design Modeler, and AQWA are performed to study the energy absorption at the nodes between the tubes. The analysis is limited to linearized hydrodynamic fluid waves loading on floating bodies by employing three-dimensional radiation/diffraction theory in regular waves in the frequency domain. Three sets of tests are conducted by varying total tube number, each tube length and the order of tubes with different lengths. After a systematic study in the frequency domain, the optimal size and number of the genetic attenuator is recommended.
