A quantitative study of isobaric equilibrium and gravity anomalies in the hawaiian islands

The deformation of a strong elastic lithosphere supported by an underlying weak magma is calculated for a long mountainous load. The deformations, produce vertical superposed stresses in the lithosphere that contribute to the support of the mountain and distribute its weight over a large area.Employing the principle of isobaric equilibrium, the distribution of the vertical supporting stress and the associated gravity anomalies may be determined by analysis.The results of the analysis are applied to the Hawaiian chain and it is shown that the calculated physical properties and gravity anomalies are remarkably like those observed. It is inferred from the study that: (a) a strong lithosphere underlies the Hawaiians and this section is practically identical with those underlying other regions; (b) the lithosphere will support one-sided stresses approximating 10⁹ dynes/cm.² for long periods of time; (c) the distribution of gravity anomaly may be described quantitatively in terms of the calculated deformations; (d) the principle of isobaric equilibrium is obeyed throughout the region whereas the isostatic principle is generally violated; and (e) the distribution of compensating masses is not at all like that demanded by the principle of isostasy.It is concluded that isostasy leads to results that are clearly wrong when applied to mountains or other deformed regions. The principle of isobaric equilibrium appears, however, to be well established by the investigation.     

A quantitative evaluation of the influence of the lithosphere on the anomalies of gravity

A quantitative investigation is made of the influence of a strong elastic lithosphere on departures from isostasy. Isostasy is shown to be a special case of a more general principle that may be called the principle of isobaric equilibrium. This principle which expresses the condition for vertical equilibrium is formulated quantitatively both in terms of the resultant vertical stresses in the lithosphere and in terms of measurable gravity anomalies. Employing the principle, a stress function may be determined that permits an estimate of the fraction of the uniform superposed load carried by the lithosphere. By applying this method, it is found that for the central region of a block to be in substantial isostatic adjustment (96 per cent.), the linear dimension of the load must approximate characterizing the elastic deformations of the lithosphere is determined by appeal to geological data from deltas and regions near a thrust fault. The values so obtained suggest a value of 50 ± 15 Km. for the effective thickness of the lithosphere. The deformed figures of the lithosphere for certain special types of load have been worked out together with the stress function that measures both the gravity anomaly and the resultant vertical stress.     

中国大陆热流分布特征及热-构造分区

根据中国大陆822个实测热流数据,研究了中国大陆主要构造单元的深部地热特征,包括40km深度的地温值、热岩石圈厚度、岩石圈累积强度和有效弹性层厚度(EET)等.结果显示,中国大陆热流的空间分布以及岩石圈热状态和流变学特征均表现出明显的横向非均匀性.这源于太平洋板块俯冲和印度-亚洲碰撞导致的新生代构造热活动.根据热流值和深部地热参数,中国大陆可以划分为东部、中部和西部三个大尺度热-构造区.     

Massive lithospheric delamination in southeastern Tibet facilitating continental extrusion

Significant left-lateral movement along the Ailao Shan-Red River fault accommodated a substantial amount of the late Eocene to early Miocene India-Asia convergence. However, the activation of this critical strike-slip fault remains poorly understood. Here, we show key seismic evidence for the occurrence of massive lithospheric delamination in southeastern Tibet. Our novel observation of reflected body waves (e.g. P₄₁₀P and P₆₆₀P) retrieved from ambient noise interferometry sheds new light on the massive foundered lithosphere currently near the bottom of the mantle transition zone beneath southeastern Tibet. By integrating the novel seismic and pre-existing geochemical observations, we highlight a linkage between massive lithospheric delamination shortly after the onset of hard collision and activation of continental extrusion along the Ailao Shan-Red River fault. This information provides critical insight into the early-stage evolution of the India-Asia collision in southeastern Tibet, which has significant implications for continental collision and its intracontinental response.     

Scalable fabrication of printed Zn//MnO2 planar micro-batteries with high volumetric energy density and exceptional safety

The rapid development of printed and microscale electronics imminently requires compatible micro-batteries (MBs) with high performance, applicable scalability, and exceptional safety, but faces great challenges from the ever-reported stacked geometry. Herein the first printed planar prototype of aqueous-based, high-safety Zn//MnO₂ MBs, with outstanding performance, aesthetic diversity, flexibility and modularization, is demonstrated, based on interdigital patterns of Zn ink as anode and MnO₂ ink as cathode, with high-conducting graphene ink as a metal-free current collector, fabricated by an industrially scalable screen-printing technique. The planar separator-free Zn//MnO₂ MBs, tested in neutral aqueous electrolyte, deliver a high volumetric capacity of 19.3 mAh/cm³ (corresponding to 393 mAh/g) at 7.5 mA/cm³, and notable volumetric energy density of 17.3 mWh/cm³, outperforming lithium thin-film batteries (≤10 mWh/cm³). Furthermore, our Zn//MnO₂ MBs present long-term cyclability having a high capacity retention of 83.9% after 1300 cycles at 5 C, which is superior to stacked Zn//MnO₂ batteries previously reported. Also, Zn//MnO₂ planar MBs exhibit exceptional flexibility without observable capacity decay under serious deformation, and remarkably serial and parallel integration of constructing bipolar cells with high voltage and capacity output. Therefore, low-cost, environmentally benign Zn//MnO₂ MBs with in-plane geometry possess huge potential as high-energy, safe, scalable and flexible microscale power sources for direction integration with printed electronics.     

塑料排水板可伸缩式插板枪的结构设计及分析

当塑料排水板手工插板枪超过5米时,由于单根长度太长携带很不方便。此外,在插板过程中,插板枪晃动等问题明显影响使用。本文设计了一种新型的塑料排水板可伸缩式插板枪结构,能在数秒钟内将两段式的插板枪便捷省力地组合成一根满足强度和刚度要求的单根插板枪并同样方便地拆卸为收缩式结构。所设计的可伸缩式插板枪在指定的栽荷作用下,由有限元分析软件计算出的各个零件最大应力均小于相对应材料的屈服极限值。不会产生永久性的变形。     

On the absorption of the hard component of the cosmic radiation

A phenomenological theory of absorption of mesotrons in the atmosphere and in dense materials at and below sea-level is given. The calculations are based on the following assumptions: (1) absorption due entirely to energy loss caused by electric interactions of charged particles and to spontaneous decay, (2) the localization of mesotron production in an equivalent layer 10 per cent. below the top of the homogeneous atmosphere, and (3) neglect of scattering. From the absorption of vertically incident mesotrons in thick layers of rock the energy distribution in the formation layer is deduced. The energy distribution at sea-level is then determined, without approximations in the analysis, and compared with observations. It is shown that fair agreement is obtained for any reasonable value of the proper lifetime but that a value of about 2 × 10^?6 sec. allows the most favorable comparison of the calculated results and the data. The integral energy distribution and the angular distribution at sea-level are obtained. For the latter it is assumed, as is plausible, that the initial angular distribution is isotropic and that the primary energy distribution is independent of the original direction of motion. The agreement between calculated and observed angular distributions is very satisfactory. The absorption in lead and in light materials for vertically incident mesotrons at sea-level is considered. The need for a more precise definition of equivalent thicknesses is pointed out and the stopping powers of lead and light substances are compared. The absorption in lead is calculated and comparison with the data indicates a slightly larger absorption than is found theoretically. However, the absorption at large lead thicknesses (over 100 cm.) and the qualitative behavior of the absorption coefficient with increasing depth below sea-level are in accord with experiment. The consideration of absorption above sea-level indicates that there should be appreciable mesotron production at elevations comparable to that of Mt. Evans (4,300 meters). This is borne out by recent observations.     

Concurrent shear stress and chemical stimulation of mechano-sensitive cells by discontinuous dielectrophoresis

Microfluidic platforms enable a variety of physical or chemical stimulation of single or multiple cells to be examined and monitored in real-time. To date, intracellular calcium signalling research is, however, predominantly focused on observing the response of cells to a single mode of stimulation; consequently, the sensitising/desensitising of cell responses under concurrent stimuli is not well studied. In this paper, we provide an extended Discontinuous Dielectrophoresis procedure to investigate the sensitising of chemical stimulation, over an extensive range of shear stress, up to 63 dyn/cm², which encompasses shear stresses experienced in the arterial and venus systems (10 to 60 dyn/cm²). Furthermore, the TRPV4-selective agonist GSK1016790A, a form of chemical stimulation, did not influence the ability of the cells'' to remain immobilised under high levels of shear stress; thus, enabling us to investigate shear stress stimulation on agonism. Our experiments revealed that shear stress sensitises GSK1016790A-evoked intracellular calcium signalling of cells in a shear-stimulus dependent manner, as observed through a reduction in the cellular response time and an increase in the pharmacological efficacy. Consequently, suggesting that the role of TRPV4 may be underestimated in endothelial cells—which experience high levels of shear stress. This study highlights the importance of conducting studies at high levels of shear stress. Additionally, our approach will be valuable for examining the effect of high levels of shear on different cell types under different conditions, as presented here for agonist activation.     

紫坪铺水库对附近断层稳定性影响的探讨

汶川地震的发生与其附近的紫坪铺水库是否有关是一个引起国际关注的问题.考虑水库的实际形状和蓄水深度,使用半无限空间的解析解,分析讨论了水库蓄水和放水过程对周围区域断层稳定性的影响.结果表明,对于倾角较小的断层面,水库放水使库区下方近地表的库仑应力有明显增加,增量达到0.2MPa,远离水库区域的库仑应力呈现象限性特征,而且随着距离的增加迅速减小.汶川地震震源落在蓄水时库仑应力减小、放水时库仑应力增加的区域内,但由于距离水库较远的原因,汶川地震前放水时库仑应力的增量只有0.005MPa左右.     

Separation by dielectrophoresis of dormant and nondormant bacterial cells of Mycobacterium smegmatis

The dielectrophoretic behavior of active, dead, and dormant Mycobacterium smegmatis bacterial cells was studied. It was found that the 72-h-old dormant cells had a much higher effective particle conductivity (812±10 μS cm⁻¹), almost double that of active cells (560±20 μS cm⁻¹), while that of dead (autoclaved) M. smegmatis cells was the highest (950±15 μS cm⁻¹) overall. It was also found that at 80 kHz, 900 μS cm⁻¹ dead cells were attracted at the edges of interdigitated castellated electrodes by positive dielectrophoresis, but dormant cells were not. Similarly, at 120 kHz, 2 μS cm⁻¹ active cells were attracted and dormant cells were not. Using these findings a dielectrophoresis-based microfluidic separation system was developed in which dead and active cells were collected from a given cell suspension, while dormant cells were eluted.     

Further studies on elastase-like activity in normal and cataractous lenses

Ca⁺⁺ was not found to be essential for the activation of the latent elastase in normal lenses. However, the activities increased 70–100% in human, bovine, sheep and goat lenses at a concentration of 5.0×10^?3M of CaCl₂. On the other hand, in cataractous human lenses, Ca⁺⁺ inhibited the process of activation. The activation process however, seems to be a divalent metal ion dependent process since ethylene diamine tetra acetate (2.0×10^?3M) blocked the activation of the elastase-like enzyme in both normal and cataractous lenses. p-Hydroxy mercuribenzoate (10^?4M) and benzamidine (1.65×10^?2M) also blocked the activation process, indicating that a trypsin-like enzyme requiring sulfhydryl groups, is involved in the activation of latent elastase.     

Magnetic losses in remanent state ferrites

Magnetic loss in remanent state ferrites¹ has generally been described through the artifice of a magnetic loss tangent (tanδ_m = μ^″?μ′). This characterization is not directly relatable to intrinsic material parameters. The results presented in this paper indicate that magnetic loss in the remanent state can be related to intrinsic material parameters by describing the ferrite mathematically by a complex “average” permeability tensor. The “average” permeability includes the effects of magnetocrystalline anistropy, remanent magnetization, linewidth and an average demagnetizing field appropriate to the distribution of magnetic domains. Experimental examples are given showing that excellent agreement is obtained between theoretically predicted and measured losses.     

Multi-scale approach for the rheological characteristics of emulsions using molecular dynamics and lattice Boltzmann method

An emulsion system was simulated under simple shear rates to analyze its rheological characteristics using a hierarchical multi-scale approach. The molecular dynamics (MD) simulation was used to describe the interface of droplets in an emulsion. The equations derived from the MD simulation relative to interfacial tension, temperature, and surfactant concentration were applied as input parameters within lattice Boltzmann method (LBM) calculations. In the LBM simulation, we calculated the relative viscosity of an emulsion under a simple shear rate along with changes in temperature, shear rate, and surfactant concentration. The equations from the MD simulation showed that the interfacial tension of the droplets tended to decrease with an increase in temperature and surfactant concentration. The relative viscosity from the LBM simulation decreased with an increase in temperature. The shear thinning phenomena explaining the inverse proportion between shear rate and viscosity were observed. An increase in the surfactant concentration caused an increase in the relative viscosity for a decane-in-water emulsion, because the increased deformation caused by the decreased interfacial tension significantly influenced the wall shear stress.     

Encapsulating metal organic framework into hollow mesoporous carbon sphere as efficient oxygen bifunctional electrocatalyst

Applying metal organic frameworks (MOFs) in electrochemical systems is a currently emerging field owing to the rich metal nodes and highly specific surface area of MOFs. However, the problems for MOFs that need to be solved urgently are poor electrical conductivity and low ion transport. Here we present a facile in situ growth method for the rational synthesis of MOFs@hollow mesoporous carbon spheres (HMCS) yolk–shell-structured hybrid material for the first time. The size of the encapsulated Zeolitic Imidazolate Framework-67 (ZIF-67) is well controlled to 100 nm due to the spatial confinement effect of HMCS, and the electrical conductivity of ZIF-67 is also increased significantly. The ZIF@HMCS-25% hybrid material obtained exhibits a highly efficient oxygen reduction reaction activity with 0.823 V (vs. reversible hydrogen electrode) half-wave potential and an even higher kinetic current density (J_K = 13.8 mA cm⁻²) than commercial Pt/C. ZIF@HMCS-25% also displays excellent oxygen evolution reaction performance and the overpotential of ZIF@HMCS-25% at 10 mA cm⁻² is 407 mV. In addition, ZIF@HMCS-25% is further employed as an air electrode for a rechargeable Zn–air battery, exhibiting a high power density (120.2 mW cm⁻² at 171.4 mA cm⁻²) and long-term charge/discharge stability (80 h at 5 mA cm⁻²). This MOFs@HMCS yolk–shell design provides a versatile method for the application of MOFs as electrocatalysts directly.     

Indian plate paleogeography,subduction and horizontal underthrusting below Tibet: paradoxes,controversies and opportunities

The India–Asia collision zone is the archetype to calibrate geological responses to continent–continent collision, but hosts a paradox: there is no orogen-wide geological record of oceanic subduction after initial collision around 60–55 Ma, yet thousands of kilometers of post-collisional subduction occurred before the arrival of unsubductable continental lithosphere that currently horizontally underlies Tibet. Kinematically restoring incipient horizontal underthrusting accurately predicts geologically estimated diachronous slab break-off, unlocking the Miocene of Himalaya–Tibet as a natural laboratory for unsubductable lithosphere convergence. Additionally, three endmember paleogeographic scenarios exist with different predictions for the nature of post-collisional subducted lithosphere but each is defended and challenged based on similar data types. This paper attempts at breaking through this impasse by identifying how the three paleogeographic scenarios each challenge paradigms in geodynamics, orogenesis, magmatism or paleogeographic reconstruction and identify opportunities for methodological advances in paleomagnetism, sediment provenance analysis, and seismology to conclusively constrain Greater Indian paleogeography.     

Release of formaldehyde during the biofiltration of methanol vapors in a peat biofilter inoculated with Pichia pastoris GS115

BackgroundMethanol can be effectively removed from air by biofiltration. However, formaldehyde is one of the first metabolic intermediates in the consumption of methanol in methylotrophic microorganisms, and it can be released out of the cell constituting a secondary emission.ResultsThe total removal of methanol was achieved up to input loads of 263 g m⁻³ h⁻¹ and the maximum elimination capacity of the system was obtained at an empty bed residence times of 90 s and reached 330 g m⁻³ h⁻¹ at an input methanol load of 414 g m⁻³ h⁻¹ and 80% of removal efficiency. Formaldehyde was detected inside the biofilter when the input methanol load was above 212 g m⁻³ h⁻¹. Biomass in the filter bed was able to degrade the formaldehyde generated, but with the increase of the methanol input load, the unconsumed formaldehyde was released outside the biofilter. The maximum concentration registered at the output of the system was 3.98 g m⁻³ when the methanol load was 672 g m⁻³ h⁻¹ in an empty bed residence times of 60 s.ConclusionsFormaldehyde is produced inside a biofilter when methanol is treated in a biofiltration system inoculated with Pichia pastoris. Biomass present in the reactor is capable of degrading the formaldehyde generated as the concentration of methanol decreases. However, high methanol loads can lead to the generation and release of formaldehyde into the environment.How to cite: Guerrero K, Arancibia A, Cáceres M, et al. Release of formaldehyde during the biofiltration of methanol vapors in a peat biofilter inoculated with Pichia pastoris GS115. Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.04.003.     

Chain matrix decompositions,continued fractions and the optimal inhomogeneous ladder networks

Studies of two-element-kind ladder networks are well known in the classical literature, among them, the most celebrated ones are due to Cauer. Driving point immittance function synthesis by using continued fractions to obtain the series and shunt arm L-C element values is a standard and routine work. The idea of introducing a class of more general networks, the inhomogeneous ladder networks, was first developed by Lee and Brown, and subsequently the synthesis techniques of such a network were established.In this paper, new results are found such as: (1) the Iff. conditions of the existence of an inhomogeneous ladder network by a given chain matrix of the network satisfying: (a) determinant of the chain matrix is 1; (b) the zeros of A(s) and z^?1B(s) or A(s) and y^?1C(s) alternate with respect to [z(s)y(s), k] with an appropriate leading set of zeros of A(s); (c) the poles of A(s) and z^?1B(s) or A(s) and y^?1C(s) are the poles of z(s)y(s) of multiplicity of n and n?1, where n the number of sections of ladder networks; (2) the Iff. condition for the inhomogeneous ladder network to be optimal is that it be antimetrical, whereas for the extended class of inhomogeneous ladder networks it is symmetrical, where an optimal inhomogeneous ladder network is defined as the corresponding network with the minimum sum of immittance levels in the series and shunt arms; (3) algorithms of synthesis procedures were developed as the by-products of the Theorems.     

板宽对FRP-混凝土粘结界面应力影响的三维有限元分析

纤维增强塑料(FRP)与混凝土的粘结性能是混凝土结构外贴FRP板材这一加固技术的重要研究课题。本文通过对混凝土表面粘贴FRP板的单剪搭接接头进行三维有限元模拟,得出了胶和混凝土中在加载端和自由端附近的各应力分量的分布曲线以及FRP板中沿板长度方向的应力分布曲线,从而分析板宽对FRP-混凝土粘结界面应力分布的具体影响,以期为进一步的相关研究提供参考。研究结果表明:(1)沿着板宽度方向应力存在着严重的不均匀性;(2)随着板宽的增加,使得应力沿着板宽的方向渐趋于均匀,因而有利于应力的传递;(3)当宽度比较大时,易发生自由端混凝土的拉剪破坏。     

Release of formaldehyde during the biofiltration of methanol vapors in a peat biofilter inoculated with Pichia pastoris GS115

BackgroundMethanol can be effectively removed from air by biofiltration (Shareefdeen et al., 1993; Babbitt et al., 2009 [1,2]). However, formaldehyde is one of the first metabolic intermediates in the consumption of methanol in methylotrophic microorganisms (Negruţa et al., 2010 [3]), and it can be released out of the cell constituting a secondary emission.ResultsThe total removal of methanol was achieved up to input loads of 263 g m⁻³ h⁻¹ and the maximum elimination capacity of the system was obtained at an empty bed residence times of 90 s and reached 330 g m⁻³ h⁻¹ at an input methanol load of 414 g m⁻³ h⁻¹ and 80% of removal efficiency. Formaldehyde was detected inside the biofilter when the input methanol load was above 212 g m⁻³ h⁻¹. Biomass in the filter bed was able to degrade the formaldehyde generated, but with the increase of the methanol input load, the unconsumed formaldehyde was released outside the biofilter. The maximum concentration registered at the output of the system was 3.98 g m⁻³ when the methanol load was 672 g m⁻³ h⁻¹ in an empty bed residence times of 60 s.ConclusionsFormaldehyde is produced inside a biofilter when methanol is treated in a biofiltration system inoculated with Pichia pastoris. Biomass present in the reactor is capable of degrading the formaldehyde generated as the concentration of methanol decreases. However, high methanol loads can lead to the generation and release of formaldehyde into the environment.How to cite: Guerrero K, Arancibia A, Caceres M, et al. Release of formaldehyde during the biofiltration of methanol vapors in a peat biofilter inoculated with Pichia pastoris GS115. Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.04.003.