Results 111 to 120 of about 140,547 (299)
Research Progress and Prospect on Laser Drilling Technology
Shiyou jixie, 2016 The conventional rotary drilling usually leads to drilling tool wear, which results in frequent drill bit replacement, causing long drilling period and high cost.The laser drilling technology could greatly improve the drilling speed and shorten the ...
Zhang Shiyi +4 more
doaj
New Tehniques of Pressure Relief and Permeability Enhancement by Abrasive Jet in Coal Mine Roadways
Shiyou jixie, 2023 Pure water jet penetration in hard coal seams is deficient for low rock-breaking efficiency and complex operation.This paper presents two new techniques of pressure relief and permeability enhancement by deep penetration with abrasive jet and by radial ...
Wang Bin +6 more
doaj
Deconstructing Corporate Governance: Director Primacy Without Principle? [PDF]
, 2011 For almost eighty years now, corporate law scholarship has centered around two elementary analytical findings made in what has once been described as the “last major work of original scholarship”within the ...
Reich-Graefe, René
core +2 more sources
Advanced Science, EarlyView.A new cerebrocortical organoid model using isogenic hiPSCs with familial Alzheimer's mutations recapitulates key AD features, including amyloid‐beta and phospho‐Tau aggregation, neuronal hyperexcitability, and synapse loss. Single‐cell RNA‐seq reveals aberrant pathways in excitatory and inhibitory neurons.
Sergio R. Labra +23 more
wiley +1 more source
Rock Breaking Mechanisms and Heat Generation Analysis on High Temperature Rocks in Deep Wells
Shiyou jixie, 2021 In order to improve the rock breaking efficiency of PDC cutter in high temperature formations in deep wells, granite and sandstone are heated respectively to different temperatures to simulate the high temperature rocks at the deep bottom hole.
Chen Hao +5 more
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Eksploatacja i Niezawodność – Maintenance and ReliabilityIn this study, based on a microwave test, the discrete element program (PFC) is used to establish a microwave-assisted disc cutter rock-breaking model and explore the influence law of the positional relationship between microwave radiation and disc cutter penetration on rock-breaking efficiency, and the results show that: The improvement of the ...
Sen Wen +4 more
openaire +1 more source
Connexin43 Deficiency Leads to Ventricular Arrhythmias by Reprogramming Proline Metabolism
Advanced Science, EarlyView.The study demonstrated that connexin43 (Cx43) knockout caused arrhythmic phenotype and decreased proline content in vitro and in vivo. Mechanistically, Cx43 interacts with the amino acid transporter SNAT2 (sodium‐dependent neutral amino acid transporter), and its deficiency disrupts proline transport and metabolism.
Hangying Ying +8 more
wiley +1 more source
Numerical simulation of optimal jet angle of water jet assisted disc cutter rock breaking
Meitan kexue jishuIn order to solve the problems of difficulty in tunneling, serious tool loss and low efficiency of breaking ultra-high strength rock encountered in the construction process of traditional hob, high-pressure water jet has become a new method to improve ...
Anxin WANG +5 more
doaj +1 more source
Energy Exploration & ExploitationTo expedite drilling operations in hard rock of coal mines, a new type of impact-shear drill bit was developed, and its mechanism of speed-up and efficiency increase was studied. The RHT constitutive model was used to describe the structural behavior of rock, and the rock-breaking simulation model of full-size bit was established.
Pei Ju, Dongzhuang Tian
openaire +2 more sources
The chemical bond as an emergent phenomenon
, 2017 We first argue that the covalent bond and the various closed-shell interactions can be thought of as symmetry broken versions of one and the same interaction, viz., the multi-center bond.
Golden, Jon C. +2 more
core +1 more source