Deep-large faults controlling on the distribution of the venting gas hydrate system in the middle of the Qiongdongnan Basin, South China Sea

Many locations with concentrated hydrates at vents have confirmed the presence of abundant thermogenic gas in the middle of the Qiongdongnan Basin(QDNB).However,the impact of deep structures on gasbearing fluids migration and gas hydrates distribution in tectonically inactive regions is still unclear.In this study,the authors apply high-resolution 3D seismic and logging while drilling(LWD)data from the middle of the QDNB to investigate the influence of deep-large faults on gas chimneys and preferred gasescape pipes.The findings reveal the following:(1)Two significant deep-large faults,F1 and F2,developed on the edge of the Songnan Low Uplift,control the dominant migration of thermogenic hydrocarbons and determine the initial locations of gas chimneys.(2)The formation of gas chimneys is likely related to fault activation and reactivation.Gas chimney 1 is primarily arises from convergent fluid migration resulting from the intersection of the two faults,while the gas chimney 2 benefits from a steeper fault plane and shorter migration distance of fault F2.(3)Most gas-escape pipes are situated near the apex of the two faults.Their reactivations facilitate free gas flow into the GHSZ and contribute to the formation of fracture‐filling hydrates.

Effect of safety valve types on the gas venting behavior and thermal runaway hazard severity of large-format prismatic lithium iron phosphate batteries

The safety valve is an important component to ensure the safe operation of lithium-ion batteries(LIBs).However,the effect of safety valve type on the thermal runaway(TR)and gas venting behavior of LIBs,as well as the TR hazard severity of LIBs,are not known.In this paper,the TR and gas venting behavior of three 100 A h lithium iron phosphate(LFP)batteries with different safety valves are investigated under overheating.Compared to previous studies,the main contribution of this work is in studying and evaluating the effect of gas venting behavior and TR hazard severity of LFP batteries with three safety valve types.Two significant results are obtained:(Ⅰ)the safety valve type dominates over gas venting pressure of battery during safety venting,the maximum gas venting pressure of LFP batteries with a round safety valve is 3320 Pa,which is one order of magnitude higher than other batteries with oval or cavity safety valve;(Ⅱ)the LFP battery with oval safety valve has the lowest TR hazard as shown by the TR hazard assessment model based on gray-fuzzy analytic hierarchy process.This study reveals the effect of safety valve type on TR and gas venting,providing a clear direction for the safety valve design.

Simulation on venting process and valve opening control method for gas trunk pipelines

Determining the venting time of a gas trunk pipeline segment provides an important basis for formulating an emergency plan in the advent of unexpected accidents.As the natural gas venting process corresponds to the transient flow,it is necessary to establish a transient hydraulic-thermal simulation model in order to determine the venting time.In this paper,based on two kinds of venting scenarios in which there is only one venting point in the venting system of a gas trunk pipeline segment—namely,where the venting point is either at one of the two ends or at the junction of two gas trunk pipeline segments—transient hydraulic-thermal simulation models are established.The models consist of gas flow governing equations,the gas state equation,gas physical property equations,initial conditions,and appropriate boundary conditions.The implicit central difference method is used to discretize the gas flow partial differential equations,and the trust-region-dogleg algorithm is used to solve the equations corresponding to each time step,in order to dynamically simulate the whole venting process.The judgment condition for the end of the venting process is that the average pressure of gas trunk pipeline segment is less than 0.11 MPa(actual pressure).Comparing the simulation results of the proposed model with those of the OLGA software and real operational data,we find that the venting time error is less than 10%.On this basis,a venting valve opening control principle is proposed,which prevents the venting noise from exceeded the specified noise value(85 d B)in the venting design of domestic gas pipeline projects.The established calculation model for venting time(dynamic simulation model)for a gas trunk pipeline segment and the proposed opening control principle of venting valve provide reference for the optimal operation of gas pipeline venting systems.

Left Ventricular Pseudoaneurysm Caused by a Left Ventricular Venting Catheter via the Right Superior Pulmonary Vein during Thoracic Aortic Surgery: A Case Report

A left ventricular (LV) pseudoaneurysm is one of the complications of acute myocardial infarction. It is also reported after chest trauma, cardiac surgery, and endocarditis. We report a rare case of an LV pseudoaneurysm induced by an LV venting catheter through the right superior pulmonary vein during thoracic aortic surgery. A 77-year-old man was referred for surgical repair of a distal aortic arch aneurysm. He underwent total aortic arch reconstruction with the frozen elephant trunk technique. The early postoperative period was uneventful. Postoperative contrast computed tomography and transthoracic echocardiography (TTE) revealed a pseudoaneurysm with a narrow neck at the apex of the LV that had sub-clinically progressed. Because of the risk of spontaneous rupture, an urgent aneurysmectomy was performed via a repeat sternotomy. Under cardioplegic arrest, the pseudoaneurysm was opened and the small orifice, which communicated with the LV, was confirmed. No myocardial ischemic changes were observed around the orifice. The pseudoaneurysm was thought to be induced by endocardial laceration by the tip of the venting catheter. The pseudoaneurysm was closed by linear repair reinforced with felt strips. The patient recovered well and was discharged 18 days after the second surgery. TTE showed no recurrence of LV aneurysm at the last follow-up.

Filtered Containment Venting： Reasons, Technology,Impact on Environment

The AREVA FCVS （filtered containment venting system） is a product family that minimizes the environmental impact incase of a severe accident in a nuclear power plant. It is based on a large-scale test and qualification program as well as on the design,licensing and installation of more than 80 projects worldwide. The product family provides flexibility regarding adaptation toaccident scenarios, applicable codes and standards, seismic design, supply chain, implementation and localization. AREVA has broadexperience in managing fleet supplies, successful licensing support and cooperation with original equipment manufacturers ofpressurized and boiling water reactors.

TURBULENCE, VORTEX AND EXTERNAL EXPLOSION INDUCED BY VENTING

The process of explosion venting to air in a cylindrical vent vessel connected to a duct, filling with a stoichiometric methane-oxygen gas mixture, was simulated numerically by using a colocated grid SIMPLE scheme based on k-epsilon turbulent model and Eddy-dissipation combustion model. The characteristics of the combustible cloud, flame and pressure distribution in the external flow field during venting were analyzed in terms of the predicted results.The results show that the external explosion is generated due to violent turbulent combustion in the high pressure region within the external combustible cloud ignited by a jet flame. And the turbulence and vortex in the external flow field were also discussed in detail. After the jet flame penetrating into the external combustible cloud, the turbulent intensity is greater in the regions with greater average kinetic energy gradient, rather than in the flame front; and the vortex in the external flow field is generated primarily due to the baroclinic effect, which is greater in the regions where the pressure and density gradients are nearly perpendicular.

Importance of LV Venting after ECMO Implantation in Post-Cardiotomy Syndrome: A Case Report

Prolonged cardiorespiratory support can be achieved with ECMO that may provide time for myocardial recovery, prevent multiorgan dysfunction and reduce mortality. Left ventricle (LV) distension can worsen already distended and hypocontractile heart. Early recognition and aggressive management of LV distension are essential for the treatment of patients with low cardiac output. The case report presented intends to show advantages of left ventricular venting on ECMO after post-cardiotomy shock. With direct flow measurements on bypass-grafts before and after the vent implantation, it was possible to clearly demonstrate the importance of venting for myocardial perfusion.

VELA■呼吸机常见两例故障分析及排除

VELA■呼吸机可进行有创和无创通气,适用于急诊病房、重症监护病房(intensive care unit,ICU)、普通病房使用,最小潮气量可至50 mL,适合于儿童患者。内置涡轮依据主板校准数据精准运行,还可根据使用环境进行校准补偿,尤其是在高海拔地区^([1]),扩大了呼吸机的应用范围。

Fundamental influences of particles on stirred and unstirred venting processes of foaming systems

Venting is the common safety measure to protect plant equipment against excessive overpressure. So far, scenarios in which particles were part of the system and should have been accounted for did ignore their presence; the scenarios were treated like a two-phase system. Current research shows that particles can have a major influence on the venting behaviour. Experimental results indicate that particles affect level swell and relief flow especially of foamy systems. Based on those results four different layers of influence of the particle have been identified and are presented in a first model. Based on this model recommendations for the development of new and more complex models are given.

Neon venting of activated NEG-coated beam pipes in IHEP

Background In High Energy Photon Source(HEPS)the beam vacuum pipes employ TiZrVHf non-evaporable getter(NEG)coatings in order to meet the operation requirements.In many occasions it is inevitable to bring the sectors to atmosphere in order to open detectors,insert or change faulty parts.Consequently,NEG coatings will be saturated and followed with activation to restore the vacuum.Such an intervention would require heating up the whole sector to hundreds of degree and last from 2 to 4 weeks.Purpose Therefore,a Neon venting system is developed in HEPS in order to perform fast interventions without losing much of the performance of the activated NEG coating.Methods Preliminary experiments has been carried out to test the venting with Neon of different purity by comparing pumping speed lost and vacuum recovery before and after Neon venting.Results Results show that Neon with ultrahigh purity(purified by NEG cartridge purifier)could preserve full pumping performance of the NEG coated pipes.Neon with 6 N purity could preserve half pumping performance of the NEG coated pipes,but vacuum could be fully restored in only 2 days.Neon with 5 N purity could saturate the NEG coated pipes,leading to full pumping performance lost.Therefore,Neon with 6 N purity or above is promising in applications of efficient operations in HEPS.

Active Air Venting of Mold Cavity to Improve Performance of Injection Molded Direct Joining

A surface micro-/nano-structured metal plate can be joined with an injection molded plastic piece in a mold,which has been named injection molded direct joining(IMDJ).The injected plastic melt infiltrates the micro-/nano-structure,e.g.,a porous structure with micro/nano pores,on the metal plate while flowing in the mold cavity where the metal plate is inserted.After solidification of the plastic,the metal and plastic materials are directly joined via the micro-/nano-structured metal surface.Since air is trapped by the plastic melt,it is easily imagined that the air in the mold cavity prevents the melt plastic from contacting the metal surface and infiltrating the micro-/nano-structure,which could result in poorer joining performance.To avoid the prevention of the air for the better joining performance,the present study proposes a system actively venting the mold cavity during injection molding.To apply the active venting to IMDJ,venting and sealing systems were newly developed.In addition,a system measuring air pressure of the mold cavity was developed.The proposed system was evaluated by a measurement of joining strengths of IMDJ specimens that were produced under various conditions.From the results,it is concluded that the active venting does not necessarily have a positive effect in any cases:the effect depends on the type of surface micro-/nano-structure.

雄构树花序化学成分研究

目的 :研究雄构树Broussonetiapapyrifera(L )Vent花序的化学成分。方法 :利用硅胶柱色谱分离纯化 ,根据化合物的光谱数据进行结构鉴定。结果 :从雄构树花序中得到 4个化合物 ,鉴定分别为 5 甲基 3 十四烷基戊内酯 (5 methyl 3 tetradecyl 5 pentandide,Ⅰ )、二十四碳烷醇 (Tetracosanol,Ⅱ )、尿嘧啶 (uracil,Ⅲ )、正十六碳酸 (hexadecylicacid ,Ⅳ )。结论 :化合物Ⅰ～Ⅳ为首次从该植物中分离得到。

野生植物构树的生物学、生态学及园林应用

构树[Broussonetia papyrifera(L.)Vent.]的自然更新机制完善、适应性强、分布广泛,具有观赏价值和生态效益,是城市园林绿化的潜在树种资源。对野生植物构树的主要生物学、生态学特征及其在园林上的应用进行了综述。

杂交构树茎段组织培养体系的建立

以杂交构树[Broussonetia papyrifera (L.) Vent.]——中科一号为试验材料,通过对杂交构树茎段的离体培养和扩繁,探究了不同激素配比对杂交构树诱导愈伤、丛生芽、壮苗和生根的影响。试验结果表明,以具腋芽的构树茎段为外植体材料,75%乙醇溶液浸泡40 s后,再经0.3%HgCl2灭菌15 min,外植体的成活率可达44%;诱导愈伤组织的最佳培养基为MS+IBA 0.5 mg/L+6-BA 2.0 mg/L+蔗糖25 g/L+琼脂7.0 g/L,pH 5.6～5.8,愈伤诱导率达90%;诱导丛生芽的最佳培养基为MS+IBA 1.5 mg/L+6-BA2.0 mg/L+蔗糖25 g/L+琼脂7.0 g/L,pH 5.6～5.8,丛生芽增殖系数为4.2,生长势较好;壮苗的最佳培养基为MS+IBA 0.2 mg/L+6-BA 1.5 mg/L+蔗糖25 g/L+琼脂7.0 g/L,pH 5.6～5.8,平均株高4.8 cm;生根的最佳培养基为1/2 MS+IBA 0.8 mg/L+活性炭1.5 g/L+马铃薯50 g/L+蔗糖25 g/L+琼脂7.0 g/L,pH 5.6～5.8,生根率100%。最佳的炼苗移栽基质土为珍珠岩∶蛭石∶草炭=1∶1∶1的混合基质,幼苗生长得最好,平均株高为7.3 cm。

Simulation of the Effects of Several Factors on Arc Plasma Behavior in Low Voltage Circuit Breaker

Taking into account the properties of the arc plasma and the electromagnetic, heat and radiative phenomena, commercial computational fluid dynamics software PHOENICS has been adapted and modified to develop the three-dimensional magneto-hydrodynamic （MHD） model of arc in a low voltage circuit breaker. The effects of the arc ignition location, venting size and gassing material on arc behavior have been investigated. The analysis of the results show that the arc velocity accelerates with the increase in the distance between arc ignition location and of the venting size, and the existence of the gassing material is beneficial to improving the arc voltage and reducing the arc temperature.

不同轮作模式对两种食用菌产量和品质的影响

为改善竹荪单作产量逐年降低问题,以长裙竹荪[Dictyophora indusiata(Vent.Pers.)Fisch.]和羊肚菌(Morchella vulgaris)为材料,设计长裙竹荪单作、羊肚菌单作、长裙竹荪-羊肚菌轮作、长裙竹荪-圆白菜轮作、羊肚菌-辣椒轮作对比试验,连续3年测定单位面积长裙竹荪和羊肚菌产量和部分品质指标。结果表明,与单作相比,轮作能够一定程度上提高长裙竹荪和羊肚菌产量及品质,其中羊肚菌-长裙竹荪轮作下二者的综合表现最好。羊肚菌-长裙竹荪轮作中长裙竹荪产量、单位面积子实体平均产出数量、去盖单株鲜重在栽培第2年和第3年均较单作显著增加,菌盖鲜重、菌高、菌柄直径和伞裙长度均显著增大,灰分、粗蛋白、粗脂肪和粗纤维含量较单作也略有增加,但二者间差异不显著;在栽培第2年和第3年,羊肚菌-长裙竹荪轮作下羊肚菌产量、子实体平均单株鲜重、单位面积子实体平均产出数量均较单作显著增加,羊肚菌灰分、粗脂肪和粗纤维含量均较单作显著增高,羊肚菌伞裙长度和菌柄直径在栽植第3年也较单作有所增大,菌盖与菌柄比大幅提高。羊肚菌-长裙竹荪轮作下羊肚菌形态、质量均显著提升。

Permeable Steel and Its Application in Plastic-injection Mould

The gas in plastics mould has great influence on performance, appearance and lifespan of the injection molded parts. Venting channel and its appendix system should be used for gas exhausting in general. However, the dependence on the venting system complicates the mould design. Furthermore in certain condition, it is difficult to integrate the venting system into the mould. Currently a kind of mold material which has gas permeability has been developed in abroad, but the applications of this mold material were restricted by its higher cost and smaller size. In this research, a porous material which was made by powder metallurgy was applied to plastic mould to replace the venting system. Permeability of the steel with different secondary processing was tested and compared with a special apparatus. The metallographic samples of the steel with different secondary processing were prepared and investigated. Finally an actual injection set was established to investigate the applications of permeable steel. The metallographies indicate that the micro-holes inside permeable steel were interconnected. Moulds made of permeable steel exhibit good permeability in the plastic-injection experiments and gas generated in the mould cavity was smoothly exhausted. The melted plastic did not penetrate into the mould or block in the micro-holes. After several times of plastic-injection experiments, the mould still retained good permeability. The strength of this permeable steel is between 200–250 MPa and suitable for industrial applications. The venting systems simplified by permeable steel in plastic-injection have simple structures, which can be applied into any place that requires gas exhausting.

Converting Tsunami Wave Heights to Earthquake Magnitudes

There is a fairly strict relation between maximum tsunami wave heights and causation earthquake magnitudes. This provides a new tool for estimating the magnitude of past earthquakes from the observed wave heights of related paleo-tsunami events. The method is subjected to a test versus two paleoseismic events with multiple independent estimates of corresponding earthquake magnitude. The agreement to the tsunami wave height conversion is good, confirming very high magnitudes of M 8.5 - 9.0 and M 8.4 - 8.5. Applying the same method to two Late Holocene events of methane venting tectonics indicates a ground shaking of forces equivalent to a M 8.0 earthquake, seriously changing previous long-term crustal hazard assessments.

The Kaali Impact as Trigger of a Mega-Tsunami Event and Violent Seismotectonics in Sweden

A meteorite impacted the ground in Estonia forming the Kaali Crater dated at 1183 - 1162 BC. It set up a Baltic-wide mega-tsunami dated at 1171 absolute varve years BC. It also triggered violent seismotectonic effect in Sweden. Ancient legends testify of direct observations of the sky phenomena and personal experiences of the ground shaking and tsunami flooding, which makes the Kaali Crater the oldest impact event documented by humans. The Ragnarök apocalypse is likely to lead its origin from the violent geodynamic activity along the Swedish east coast.

煤矿通风系统现状可视化仿真研究

根据某矿通风系统的应用现状,运用矿井通风可视化仿真系统Vent GIS对该矿的通风系统现状进行了可视化仿真,主要包括通风仿真系统的构建,通风网络拓扑关系的自动创建,仿真系统基础数据可视化检查,通风系统相关图形的自动生成,通风机特性可视化仿真,通风系统三维可视化仿真以及风流分配仿真,最终得出合理的风流分配方案。