Results 91 to 100 of about 922,670 (302)
Dynamics of Circumferential Torque Hydraulic Shock Generator
Shiyou jixie, 2015 The circumferential torque hydraulic shock generator may effectively inhibit "stuck and slip" during the process of drilling operations.This paper presents the structure and principles of the circumferential torque hydraulic shock generator,and provides ...
Li Meiqiu +4 more
doaj
Evolution of penetration mechanism induced by strain rate effect
EPJ Web of Conferences, 2018 According to the dynamic mechanical properties, in the striking velocity range, the strain rate of the projectile and target caused by penetration can reach 104~106 /s. The strain rate effect increases sharply and then tends to saturation.
Li Gan, Song Chunming, Wang Mingyang
doaj +1 more source
FEBS Letters, EarlyView.The Ile181Asn variant of human UDP‐xylose synthase (hUXS1), associated with a short‐stature genetic syndrome, has previously been reported as inactive. Our findings demonstrate that Ile181Asn‐hUXS1 retains catalytic activity similar to the wild‐type but exhibits reduced stability, a looser oligomeric state, and an increased tendency to precipitate ...
Tuo Li +2 more
wiley +1 more source
Determining whether estimated spore release rates for Aspergillus fumigatus are compatible with their measured growth rates in composting systems [PDF]
, 2008 The composting process like other waste management activities has the potential to generate large concentrations of bioaerosols which can be widely dispersed into the surrounding environment.
Fletcher, L.A. +2 more
core +1 more source
Structural Design and Performance Analysis of Novel Torsional Impact Tool
Shiyou jixie, 2017 The existing impact and rotary-impact rock breaking technology mostly use the axial impact and the shear action of the PDC bit to achieve high-efficiency rock breaking, but excessive axial force will cause the failure of PDC bit shear force, resulting in
Fu Chuanhong +5 more
doaj
Consumer Learning and Hybrid Vehicle Adoption [PDF]
We study the diffusion of hybrid vehicles among consumers. Using data on sales of 11 different models over seven years, we identify the effect of the penetration rate--total cumulative hybrid sales per capita--on new hybrid purchases.
Heutel, Garth, Muehlegger, Erich
core +1 more source
FEBS Letters, EarlyView.We reconstituted Synechocystis glycogen synthesis in vitro from purified enzymes and showed that two GlgA isoenzymes produce glycogen with different architectures: GlgA1 yields denser, highly branched glycogen, whereas GlgA2 synthesizes longer, less‐branched chains.
Kenric Lee +3 more
wiley +1 more source
Factors Affecting Penetration Rate
Journal of the Japanese Association for Petroleum Technology, 1965 By the use of drilling records taken in oil fields in Japan, the factors affecting penetration rate of a rotary drilling were analysed. Some of the results obtained are as follows: (1) In some fields there is a relationship between load on a bit and penetration rate both for vertical wells and directional wells drilled with a vertical deviation angle ...
openaire +2 more sources
Optimal bit selection for large-diameter wellbore drilling in an ultra-deep well
Petroleum Exploration and DevelopmentTo optimize the bit selection for large-diameter wellbore in the upper section of an ultra-deep well S-1, a full-well dynamic model integrating drill string vibration and bit rock-breaking was established and then verified using measured vibration data ...
Lili CHEN +7 more
doaj +1 more source
Prediction for Rate of Penetration Based on PCA-BP Algorithm
Shiyou jixie, 2023 Rate of penetration(ROP)is an important index to measure drilling efficiency.Accurate prediction of ROP plays an important role in improving drilling efficiency and reducing costs,but the commonly used ROP equation prediction model has difficulties in ...
Tang Ming +4 more
doaj