Trench型N-Channel MOSFET低剂量率效应研究

基于抗辐射100V Trench型N-Channel MOSFET开展了不同剂量率的总剂量辐射实验并进行了分析,创新性提出了器件随低剂量率累积以及不同偏置状态下的变化趋势和机理,给出了器件实验前后的转移曲线和直流参数,进行了二维数值仿真比较,证明了实验和仿真的一致性。研究表明:随高剂量率的剂量增加,器件阈值电压(V_(TH))发生了明显负向漂移现象,导通电阻(R_(DSON))出现5%左右的降低,击穿电压(BV_(DS))保持基本不变;低剂量率下总剂量效应与高剂量率有明显不同,阈值电压漂移量减小,同时出现正向漂移现象;此时导通电阻(R_(DSON))和击穿电压(BV_(DS))较高剂量率变化量进一步下降。研究认为,低剂量率下器件界面缺陷电荷增加变多,使得阈值电压的漂移方向发生改变,同时低剂量率实验周期是高剂量率的500倍,退火效应也较高剂量率的明显,导致器件参数辐射前后差异性减小。

The Origins of the Arc-Shaped Langshan Uplift and Linhe Trench

In the northern part of the Ordos Basin, there is a 325 km long arc-shaped Langshan uplift and a 15 km-deep Linhe Trench in front of Langshan, which are rare geological phenomena for which origins no one has explained. This article comprehensively analyzes the research achievements over the past 40 years of geology, geomorphology, seismic exploration, paleogeography, and oil and gas exploration in the Ordos Basin and Langshan. It recognizes that the northern part of the Ordos Basin experienced a meteorite impact in the Late Cretaceous period. The impact pushed the block northwest ward, subducting after colliding with igneous rocks in the north. This sudden event formed a clear arc-shaped mountain zone in the north and a wedge-shaped trench in front of the mountain. The chaotic layers, prolonged and continuous faults, and numerous thrust layers in the Langshan, a negative anomaly area in the center of the northern Ordos, abnormal orientation of crystalline basement structures in the north of Ordos, Moho uplift, and distribution of meteorite fragments in the northwest of Langshan, all of these geological phenomena support the occurrence of the meteorite impact event, forming the arc-shaped Langshan and the Trench.

Blast injury risks to humans within a military trench

In land warfare,trenches serve as vital defensive fortifications,offering protection to soldiers while engaging in combat.However,despite their protective function,soldiers often sustain injuries within these trenches.The lack of corresponding blast data alongside empirical injury reports presents a significant knowledge gap,particularly concerning the blast pressures propagating within trench spaces following nearby explosions.This absence hinders the correlation between blast parameters,trench geometry,and reported injury cases,limiting our understanding of blast-related risks within trenches.This paper addresses the critical aspect of blast propagation within trench systems,essential for evaluating potential blast injury risks to individuals within these structures.Through advanced computational fluid dynamics(CFD)simulations,the study comprehensively investigates blast injury risks resulting from explosions near military trenches.Employing a sophisticated computational model,the research analyzes the dynamic blast effects within trenches,considering both geometrical parameters and blast characteristics influenced by explosive weight and scaled distance.The numerical simulations yield valuable insights into the impact of these parameters on blast injury risks,particularly focusing on eardrum rupture,lung injury,and traumatic brain injury levels within the trench.The findings elucidate distinct patterns of high-risk zones,highlighting unique characteristics of internal explosions due to confinement and venting dynamics along the trench.This study underscores the significance of detailed numerical modeling in assessing blast injury risks and provides a novel knowledge base for understanding risks associated with explosives detonating near military trenches.The insights gained contribute to enhancing safety measures in both military and civilian contexts exposed to blast events near trench structures.

Physical insights into trapping effects on vertical GaN-on-Si trench MOSFETs from TCAD

Vertical GaN power MOSFET is a novel technology that offers great potential for power switching applications.Being still in an early development phase,vertical GaN devices are yet to be fully optimized and require careful studies to foster their development.In this work,we report on the physical insights into device performance improvements obtained during the development of vertical GaN-on-Si trench MOSFETs(TMOS’s)provided by TCAD simulations,enhancing the dependability of the adopted process optimization approaches.Specifically,two different TMOS devices are compared in terms of transfer-curve hysteresis(H)and subthreshold slope(SS),showing a≈75%H reduction along with a≈30%SS decrease.Simulations allow attributing the achieved improvements to a decrease in the border and interface traps,respectively.A sensitivity analysis is also carried out,allowing to quantify the additional trap density reduction required to minimize both figures of merit.

一种抗辐射Trench型N 30 V MOSFET器件设计

由于Trench结构在降低元胞单元尺寸、提升沟道密度和消除JFET区电阻等方面的优势,Trench型MOSFET已广泛应用于低压产品领域。在研究抗辐射机理和抗辐射加固技术的基础上,设计了一款新型抗辐射Trench型N30VMOSFET器件。实验结果显示,产品击穿电压典型值达42V,特征导通电阻为51mΩ·mm^(2)。在^(60)Co γ射线100krad(Si)条件下,器件阈值电压漂移仅为-0.3V,漏源漏电流从34nA仅上升到60nA。采用能量为2006MeV、硅中射程为116μm、线性能量传输(LET)值为75.4MeV·cm^(2)/mg的^(118)Ta离子垂直入射该器件,未发生单粒子事件。

Submarine Trenches and Wave-Wave Interactions Enhance the Sediment Resuspension Induced by Internal Solitary Waves

Internal solitary waves(ISWs)are nonlinear fluctuations in nature that could cause significant interactions between seawater and the seabed.ISWs have been proven to be an adequate cause of sediment resuspension in shallow and deep-sea environments.In the South China Sea,ISWs have the largest amplitude globally and directly interact with the seabed near the Dongsha slope in the northern South China Sea.We analyzed the water profile and high-resolution multibeam bathymetric data near the Dongsha slope and revealed that submarine trenches have a significant impact on the sediment resuspension by ISWs.Moreover,ISWs in the zone of the wave-wave interaction enhanced sediment mixing and resuspension.The concentration of the suspended particulate matter inside submarine trenches was significantly higher than that outside them.The concentration of the suspended particulate matter near the bottoms of trenches could be double that outside them and formed a vast bottom nepheloid layer.Trenches could increase the concentration of the suspended particulate matter in the entire water column,and a water column with a high concentration of the suspended particulate matter was formed above the trench.ISWs in the wave-wave interaction zone near Dongsha could induce twice the concentration of the bottom nepheloid layer than those in other areas.The sediment resuspension caused by ISWs is a widespread occurrence all around the world.The findings of this study can offer new insights into the influence of submarine trench and wave-wave interaction on sediment resuspension and help in geohazard assessment.

Lateral downslope transport and tentative sedimentary organic carbon box model in the southern Yap Trench,western Pacific Ocean

Sediment collapse and subsequent lateral downslope migration play important roles in shaping the habitats and regulating sedimentary organic carbon(SOC)cycling in hadal trenches.In this study,three sediment cores were collected using a human-occupied vehicle across the axis of the southern Yap Trench(SYT).The total organic carbon(TOC)and total nitrogen(TN)contents,δ13C,radiocarbon ages,specific surface areas,and grain size compositions of sediments from three cores were measured.We explored the influence of the lateral downslope transport on the dispersal of the sediments and established a tentative box model for the SOC balance.In the SYT,the surface TOC content decreased with water depth and was decoupled by the funneling effect of the V-shaped hadal trench.However,the sedimentation(0.0025 cm/a)and SOC accumulation rates(∼0.038 g/(m^(2)·a)(in terms of OC))were approximately 50%higher in the deeper hadal region than in the abyssal region(0.0016 cm/a and∼0.026 g/(m^(2)·a)(in terms of OC),respectively),indicating the occurrence of lateral downslope transport.The fluctuating variations in the prokaryotic abundances and the SOC accumulation rate suggest the periodic input of surficial sediments from the shallow region.The similar average TOC(0.31%–0.38%),TN(0.06%–0.07%)contents,and SOC compositions(terrestrial OC(11%–18%),marine phytoplanktonic OC(45%–53%),and microbial OC(32%–44%))of the three sites indicate that the lateral downslope transport has a significant mixing effect on the SOC composition.The output fluxes of the laterally transported SOC(0.44–0.56 g/(m^(2)·a)(in terms of OC))contributed approximately(47%–73%)of the total SOC input,and this proportion increased with water depth.The results of this study demonstrate the importance of lateral downslope transport in the spatial distribution and development of biomes.

Characteristics of dissolved sugars in the Southern Yap Trench from sea surface to hadal zone

2,4,6-Tripyridine-s-triazine(TPTZ)spectrophotometric method was applied to determine the concentrations of dissolved monosaccharides(MCHO),polysaccharides(PCHO),and total carbohydrate(TCHO)in seawater samples collected from sea surface to hadal zone and sediment-seawater interface of the Southern Yap Trench in the Western Pacific Ocean.Results show that the concentrations of MCHO,PCHO,and TCHO ranged from 6.3 to 22.3μmol C/L,1.1 to 25.4μmol C/L,and 12.1 to 44.9μmol C/L,respectively,from the euphotic layer to the hadal zone of the trench.At different sampling stations,the concentrations of MCHO,PCHO,and TCHO in the seawater showed complex vertical variation characteristics,but the overall variation trends were decreasing with water depth.In the Southern Yap Trench,the maximum concentration of MCHO in the seawater appeared in the euphotic layer,and the minimum in the hadal zone.The maximum concentration of PCHO appeared in the euphotic layer,and the minimum in the bathypelagic layer.The water layer where the maxima and minima of the average concentration of TCHO appeared was consistent with that of PCHO.PCHO was the major component of TCHO in the seawater of the Southern Yap Trench.In the seawater from the sediment-seawater interface,the concentrations of MCHO,PCHO,and TCHO ranged from 8.4 to 10.6μmol C/L,3.8 to 5.8μmol C/L,and 12.2 to 15.2μmol C/L,respectively,and MCHO was the major component of TCHO.The key factors affecting the concentration and existing forms of dissolved sugars in the seawater of the Southern Yap Trench included photosynthesis,respiration,polysaccharide hydrolysis,adsorption and desorption of particulate matter,trench“funnel effect”,deep ocean currents,sediment resuspension,and etc.This study provided fundamental data about labile organic matter in abyss and hadal zone of marine environment,which is significant for further understanding of deep-sea organic carbon cycle.

Study on the Application of Vibration Isolation by Using a Trench in Frame Structures

An isolation trench is a simple and effective method to isolate structural vibrations originating from sources of vibration other than earthquakes(machines,traffic,explosions,etc.);however,there is still not a conclusive depth of the isolation trench for frame structures.To investigate the isolation effect of a trench in the frame structure designed for ground vibration,both a field test and finite element analysis were conducted to analyze the reduced effect of the vibration.The vibration reduction analysis was based on the dynamic equation and wave theory.Considering the vibration control of an industrial plant frame,a soil-trench-building finite element model was built to analyze the vibration characteristics of the floor before and after the open isolation trench structure was used.According to the model,a dynamic test was carried out on the frame structure to assess the effect of the vibration reduction by introducing the trench.The results showed that the depth of the trench was the dominating factor in vibration isolation.When the depth of the trench reached 1~1.3 times the wavelength of the Rayleigh wave,the damping effect was the strongest.the width of the trench has little effect on the vibration isolation efficiency,and the trench must be maintained at a certain distance from the building to ensure the vibration damping efficiency.The vibration of each floor was obviously reduced after the trench was built.The vibration damping effect of the trench was significant.

Characteristics of vertical distributions of methane and dimethylsulphoniopropionate in the southern Yap Trench

Methane(CH_(4) )and dimethylsulphoniopropionate(DMSP)are major carbon and sulfur sources for bacterioplankton in the ocean.We investigated the characteristics of CH_(4) and DMSP in the southern Yap Trench from sea surface to hadal zone in June 2017.We found that concentrations of CH_(4) varied from 1.5 to 4.5 nmol/L with saturation between 94% and 204% in the euphotic layer.Concentrations of dissolved DMSP(DMSPd)ranged from 0.5 to 3.7 nmol/L with higher values in surface water and decreased with depth.Concentrations of particulate DMSP(DMSPp)varied from 0 to 13.6 nmol/L.Concentrations of total DMSP(DMSPt)ranged 2.0-15.2 nmol/L.Their concentrations decreased slightly and reached consistent levels in 200-3000-m depth due probably to heterotrophic bacterial production in marine aphotic and high-pressure environments.An exception occurred around 4000-m depth where their concentrations increased considerably and then decreased in deeper water.This previously unrecognized phenomenon sheds light on the elevated concentrations of DMSP in the abyssal layer that might be affected by the Lower Circumpolar Deep Water(LCPW).Concentrations of CH_(4) in seawater of the Benthic Boundary Layer of the southern Yap Trench were slightly higher than those in the water column at approximate depth,and concentrations of DMSP in seawater of the Benthic Boundary Layer of the southern Yap Trench were not much higher than those in the water column at the approximate depth,indicating that sediment was a weak source of CH_(4) but was not a source of DMSP for seawater in the study area.This study presented clear correlations between CH_(4) and DMSP from sea surface to sea bottom,proving that DMSP might be a potential substrate for CH_(4) not only in oxic surface seawater but also in deep water.

SiC trench MOSFET with dual shield gate and optimized JFET layer for improved dynamic performance and safe operating area capability

A novel silicon carbide(SiC) trench metal–oxide–semiconductor field-effect transistor(MOSFET) with a dual shield gate(DSG) and optimized junction field-effect transistor(JFET) layer(ODSG-TMOS) is proposed. The combination of the DSG and optimized JFET layer not only significantly improves the device’s dynamic performance but also greatly enhances the safe operating area(SOA). Numerical analysis is carried out with Silvaco TCAD to study the performance of the proposed structure. Simulation results show that comparing with the conventional asymmetric trench MOSFET(Con-ATMOS), the specific on-resistance(Ron,sp) is significantly reduced at almost the same avalanche breakdown voltage(BVav). Moreover, the DSG structure brings about much smaller reverse transfer capacitance(Crss) and input capacitance(Ciss), which helps to reduce the gate–drain charge(Qgd) and gate charge(Qg). Therefore, the high frequency figure of merit(HFFOM) of Ron,sp·Qgdand Ron,sp· Qgfor the proposed ODSG-TMOS are improved by 83.5% and 76.4%, respectively.The switching power loss of the proposed ODSG-TMOS is 77.0% lower than that of the Con-ATMOS. In addition, the SOA of the proposed device is also enhanced. The saturation drain current(Id,sat) at a gate voltage(Vgs) of 15 V for the ODSGTMOS is reduced by 17.2% owing to the JFET effect provided by the lower shield gate(SG) at a large drain voltage. With the reduced Id,sat, the short-circuit withstand time is improved by 87.5% compared with the Con-ATMOS. The large-current turn-off capability is also improved, which is important for the widely used inductive load applications.

High performance carrier stored trench bipolar transistor with dual shielding structure

We propose a novel high performance carrier stored trench bipolar transistor(CSTBT)with dual shielding structure(DSS-CSTBT).The proposed DSS-CSTBT features a double trench structure with different trench profiles in the surface,in which a shallow gate trench is shielded by a deep emitter trench and a thick oxide layer under it.Compared with the conventional CSTBT(con-CSTBT),the proposed DSS-CSTBT not only alleviates the negative impact of the shallow gate trench and highly doped CS layer on the breakdown voltage(BV),but also well reduces the gate-collector capacitance CGC,gate charge Q_(G),and turn-off loss E_(OFF)of the device.Furthermore,lower turn-on loss E_(ON)and gate drive loss E_(DR)are also obtained.Simulation results show that with the same CS layer doping concentration N_(CS)=1.5×10^(16)cm^(-3),the BV increases from 1312 V of the con-CSTBT to 1423 V of the proposed DSS-CSTBT with oxide layer thickness under gate(T_(og2))of 1μm.Moreover,compared with the con-CSTBT,the C_(GC)at V_(CE)of 25 V and miller plateau charge(Q_(GC))for the proposed DSS-CSTBT with T_(og2)of 1μm are reduced by 79.4%and 74.3%,respectively.With the VGEincreases from 0 V to 15 V,the total QGfor the proposed DSS-CSTBT with T_(og2)of 1μm is reduced by 49.5%.As a result,at the same on-state voltage drop(V_(CEON))of 1.55 V,the E_(ON)and E_(OFF)are reduced from 20.3 mJ/cm^(2)and 19.3 mJ/cm^(2)for the con-CSTBT to8.2 mJ/cm^(2)and 9.7 mJ/cm^(2)for the proposed DSS-CSTBT with T_(og2)of 1μm,respectively.The proposed DSS-CSTBT not only significantly improves the trade-off relationship between the V_(CEON)and E_(OFF)but also greatly reduces the E_(ON).

A SiC asymmetric cell trench MOSFET with a split gate and integrated p^(+)-poly Si/SiC heterojunction freewheeling diode

A new SiC asymmetric cell trench metal–oxide–semiconductor field effect transistor(MOSFET)with a split gate(SG)and integrated p^(+)-poly Si/SiC heterojunction freewheeling diode(SGHJD-TMOS)is investigated in this article.The SG structure of the SGHJD-TMOS structure can effectively reduce the gate-drain capacitance and reduce the high gateoxide electric field.The integrated p^(+)-poly Si/SiC heterojunction freewheeling diode substantially improves body diode characteristics and reduces switching losses without degrading the static characteristics of the device.Numerical analysis results show that,compared with the conventional asymmetric cell trench MOSFET(CA-TMOS),the high-frequency figure of merit(HF-FOM,R_(on,sp)×Q_(gd,sp))is reduced by 92.5%,and the gate-oxide electric field is reduced by 75%.In addition,the forward conduction voltage drop(V_(F))and gate-drain charge(Q_(gd))are reduced from 2.90 V and 63.5μC/cm^(2) in the CA-TMOS to 1.80 V and 26.1μC/cm^(2) in the SGHJD-TMOS,respectively.Compared with the CA-TMOS,the turn-on loss(E_(on)) and turn-off loss(E_(off)) of the SGHJD-TMOS are reduced by 21.1%and 12.2%,respectively.

Vertical variations and composition of dissolved free amino acid in the seawater of the Yap Trench in the western Pacific Ocean

The composition and concentration of dissolved free amino acid(DFAA)of seawater samples collected in May 2016 from the surface to the hadal zone of the northern region of the Yap Trench were analyzed by pre-column derivatization of o-phthalaldehyde.Results show that the average concentration of DFAA in the study area was 0.47±0.36μmol/L.In different sampling stations,the concentrations of DFAA with water depth showed complex variation patterns.At the sediment-seawater interface,the concentrations of DFAA in the western side of the trench were obviously higher than that in its eastern side.In the study area,there were no significant correlations between the concentrations of DFAA and the environmental parameters such as concentrations of chlorophyll a(Chl a),dissolved oxygen(DO),pH,and dissolved inorganic nitrogen(DIN),indicating that the concentrations of DFAA in seawater of the trench are affected by many factors,such as photosynthesis,respiration,temperature,pressure,illumination,and circulation.The dominant DFAA are similar in different water layers of sampling stations,including aspartic acid(Asp),glutamic acid(Glu),glycine(Gly),and serine(Ser).The composition of different amino acids,and the relative abundance of acidic,basic,and neutral amino acids might be related to the sources and consumption of various amino acids.Nine pairs of amino acids in the DFAA showed significantly positive relationship by correlation matrix analysis,suggesting that they might share similar biogeochemical processes.The degradation index(DI)of the DFAA in seawater of the Yap Trench could reflect the degradation,source,and freshness of DFAA in the trench to some extents.This is a preliminary study of amino acids from sea surface to hadal zone in the ocean,more works shall be done in different trenches to reveal their biogeochemical characte ristics in extreme marine environme nts.

Low switching loss and increased short-circuit capability split-gate SiC trench MOSFET with p-type pillar

A split-gate SiC trench gate MOSFET with stepped thick oxide, source-connected split-gate(SG), and p-type pillar(ppillar) surrounded thick oxide shielding region(GSDP-TMOS) is investigated by Silvaco TCAD simulations. The sourceconnected SG region and p-pillar shielding region are introduced to form an effective two-level shielding, which reduces the specific gate–drain charge(Q_(gd,sp)) and the saturation current, thus reducing the switching loss and increasing the short-circuit capability. The thick oxide that surrounds a p-pillar shielding region efficiently protects gate oxide from being damaged by peaked electric field, thereby increasing the breakdown voltage(BV). Additionally, because of the high concentration in the n-type drift region, the electrons diffuse rapidly and the specific on-resistance(Ron,sp) becomes smaller.In the end, comparing with the bottom p~+ shielded trench MOSFET(GP-TMOS), the Baliga figure of merit(BFOM,BV~2/R_(on,sp)) is increased by 169.6%, and the high-frequency figure of merit(HF-FOM, R_(on,sp) × Q_(gd,sp)) is improved by310%, respectively.

泡沫轻质土回填管道沟槽路面表层动力响应研究

市政道路下伏管道沟槽常采用土、砂子、碎石等传统散体材料回填,由于沟槽空间受限,压实度难以满足设计要求,管道破损渗漏或交通荷载作用下,容易造成路面开裂,甚至塌陷。泡沫轻质土具有轻质、高强、自密实、抗渗漏等特性,可以将其应用于管道沟槽回填工程。为了研究泡沫轻质土回填管道沟槽的路面动力响应特性,以振动加速度和动位移为动力响应指标,开展泡沫轻质土回填段和中砂回填段的路面动力响应现场试验。试验车速分别为20,40和60 km/h,车重分别为空载、半载、满载,共9种试验工况。研究结果表明,泡沫轻质土回填区段测点振动加速度最大值、动位移最大值分别为31.93 mm/s^(2)、6.23μm,而中砂回填区段分别为35.79 mm/s^(2)、6.90μm。振动加速度峰值、动位移峰值均随车重、车速的增加而增大。车重由空载变为满载时,泡沫轻质土回填区段测点动位移峰值变化幅度仅为中砂回填区段测点的15.2%~51.0%;车速由20 km/h增加至60 km/h时,动位移峰值变化幅度为中砂回填区段测点的16.8%~66.8%。泡沫轻质土回填区段振动加速度峰值衰减率、动位移峰值衰减率分别为中砂回填区段的1.16~1.38倍及1.15~1.33倍,削减了沟槽回填区段路面测点振动的高频和低频成分,泡沫轻质土回填区段整体刚度较好,减振效果良好。研究成果可为泡沫轻质土回填管道沟槽的设计施工提供参考。

不同勘探方法对浅层小断距隐伏断裂探测效果

采用浅层地震勘探、钻孔联合剖面勘探、槽探3种方法联合探测临汾盆地郭家庄断裂的空间位置,并研究其活动特征。结果表明,不同探测方法对断层信息的揭示存在很大差异,浅层地震勘探在探测具有一定断距的断层,同时地层存在一定物性差异的情况下能取得理想的效果,且不同的工作参数探测效果不相同;钻孔联合剖面勘探能提高对小断距断层的分辨率,但受地形及地层主观认别等因素的影响,可能会遗漏断距小、标识层薄的断层;槽探能较好地识别地表断层的微小断距,但受施工深度和施工条件影响。3种方法相结合,可以精确确定断裂的空间位置和活动特征。

泡沫轻质土和砂土回填管道沟槽动力响应数值模拟对比分析

市政道路下覆管道回填区采用砂土等散体材料回填时,控制压实度是施工的关键技术难题之一。引入泡沫轻质土作为管道沟槽回填区材料能较好地解决回填压实度低的问题。为了研究回填管道沟槽泡沫轻质土的动力特性,结合某市政道路回填段行车激励现场试验,沿行车线路横向路面布设8个监测点,建立管道-回填区-路基路面三维动力模型,并施加不同工况下的三轴货车行车荷载激励,数值模拟结果与现场监测点实测数据对比验证了模型的可行性。运用此模型对泡沫轻质土、砂土回填区段的路基路面、管道外壁动力响应及路基工作区深度展开对比分析。结果表明:1)泡沫轻质土回填区沿深度方向动应力峰值衰减率、振动加速度衰减率分别为砂土回填区段的1.63~1.93倍及2.13~3.7倍。2)车重由空载变为满载时,泡沫轻质土回填区和砂土回填区管顶动应力峰值分别增加18.03 kPa和17.86 kPa,说明在回填区上行驶重型车辆时会导致埋地管道振动显著增加。3)泡沫轻质土、砂土回填区管顶和靠近行车一侧动位移峰值比例分别为1.31、1.96,泡沫轻质土回填区管道外壁动位移峰值分布较砂土回填区更加均匀。4)采用泡沫轻质土回填时路基动敏感区和动影响区深度分别为砂土回填的0.68~0.78倍、0.77~0.79倍,对路基稳定性有利。研究结果可为泡沫轻质土在市政道路管道沟槽回填中的相关应用提供参考。

新型旋耕开沟施肥播种机的设计与研究

针对播种施肥难的问题,结合垄作区作物种植的农艺要求,设计了一款新型旋耕开沟施肥播种机。机具适用于小麦、大豆和玉米垄上栽培技术,可实现精确深施肥、精密播种、开沟、覆土和镇压等作业,为小麦、大豆和玉米的规模化、机械化作业提供了一定的技术支撑。试验结果表明:设计的新型旋耕开沟施肥播种机对降低漏播、提高播种深度和植株距离的合格率具有重要意义,大大提高了作业质量和效率。

冷浸田起垄平整装置设计与试验

针对冷浸田终年积水、水土温度低及排水不良,需进行垄作栽培水稻的生产要求及目前缺乏相关机具的生产现状,设计了一种适宜于冷浸田作业的起垄平整装置,该装置主要由起垄辊、微垄开沟器及平整部件组成,实现大垄排水、微垄蓄水作业,利于冷浸田排水及水稻种子生长发育。根据《冷浸田机械起垄水稻栽培技术规程》,对起垄辊、微垄开沟器及平整部件关键参数进行了设计,确定起垄辊回转半径为560 mm、锥形面倒角为28°,微垄开沟器宽度为50 mm、高度为40 mm及平整部件可调节角度为5°。基于DEM-FEM耦合仿真分析确定了装置较优运行参数,当机具前进速度为0.6 m/s、旋耕刀辊转速为230 r/min、起垄辊转速为120 r/min时,土壤回流率为3.51%,并进行了起垄辊应力应变分析。田间试验结果表明,平均垄沟沟深为160.03 mm、沟顶宽为174.84 mm,平均垄顶宽为1888.89 mm,平均厢面平整度为11.26 mm,平均微垄沟沟宽为60.16 mm、沟深为36.48 mm,各项指标均满足冷浸田机械化起垄作业要求。