Deployment of Self-Propelled Modular Transporter for Vessel Installation

The traditional way of installing large vessels has always been to employ the use of cranes. The Water Handling Debottlenecking Project team has, instead, made use of a different technology—employing a Self-Propelled Modular Transporter (SPMT) to install nine vessels in situ. These SPMT units have many advantages over crane installations, such as safety and efficiency, not to mention lower costs due to their self-propelled capabilities.

Investigating the elliptic anisotropy of identified particles in p-Pb collisions with a multi-phase transport model

The elliptic azimuthal anisotropy coefficient(v_(2))of the identified particles at midrapidity(|η|<0.8)was investigated in p-Pb collisions at√s_(NN)=5.02 TeV using a multi-phase transport model(AMPT).The calculations of differential v_(2)based on the advanced flow extraction method of light flavor hadrons(pions,kaons,protons,andΛ)in small collision systems were extended to a wider transverse momentum(p_(T))range of up to 8 GeV/c for the first time.The string-melting version of the AMPT model provides a good description of the measured p_(T)-differential v_(2)of the mesons but exhibits a slight deviation from the baryon v_(2).In addition,we observed the features of mass ordering at low p_(T)and the approximate number-of-constituentquark(NCQ)scaling at intermediate p_(T).Moreover,we demonstrate that hadronic rescattering does not have a significant impact on v_(2)in p-Pb collisions for different centrality selections,whereas partonic scattering dominates in generating the elliptic anisotropy of the final particles.This study provides further insight into the origin of collective-like behavior in small collision systems and has referential value for future measurements of azimuthal anisotropy.

Effects of octreotide on glucose transporter type 2expression in obese rat small intestine

AIM： TO investigate the effects of the somatostatin analogue, octreotide, on maltose and sucrase activities and expression of glucose transporter type 2 （GLUT2） in obese rat intestinal mucosa. METHODS： We divided 49 Sprague-Dawley rats into a group of 31 high fat diet-induced obese rats and a group of 18 normal controls. The obese rats were separated into an octreotide treated group 9f 16 rats and an obese group of 15. The intervention （：jroup was injected with octreotide at 40 ±g/kg body weight every 12 h for 8 d. Rat body weight was measured weekly to calculate Lee＇s index. After euthanization, maltase and sucrase activities in the small intestine were measured by activity assays, and the fasting plasma glucose level was measured. The expression of GLUT2 in small intestinal mucosa was analyzed by immunohistochemistry, reverse transcriptase polymerase chain reaction and Western blotting assays. RESULTS： Body weight, Lee＇s index, fasting plasma glucose level, maltase activity in small intestinal mucosa, mucosa and apical GLUT2, GLUT2 mRNA and protein expression levels were all significantly higher in the obese group than in the normal control group （605.61 ± 141.00 vs 378.54 ±111.75, 337.61 ± 10.82 vs 318.73 ± 20.10, 8.60± 1.38 vs 7.33 ± 0.70, 156.01 ± 58.81 vs 50.43 ± 30.49, 390 744.2± 62 469.21 vs 170 546.50 ± 50 646.14, 26 740.18 ±3809.60 vs 354.98± 57.19, 0.26± 0.11 vs 0.07± 0.02, and 2.08 ± 0.59 vs 1.27 ± 0.38, respectively, all P 〈 0.01）. Sucrase activity did not differ between the two groups. Octreotide intervention significantly decreased the body weight and fasting plasma glucose level of obese rats （508.27 ± 94.39 vs 605.61 ± 141.00, 7.58 ± 1.51 vs 8.60±1.38, respectively, all P 〈 0.05）. The intestinal mucosa and apical GLUT2, expression of GLUT2 mRNA and protein were also significantly lower in the octreotide intervention group than in the obese group （269 975.2 ± 53 730.94 vs 390 744.2 ± 62 469.21, 3758.06 ± 364.51 vs 26 740.18 ± 3809.60, 0.08 ± 0.02 vs 0.26 ±0.11, and 1.31 ± 0.27 vs 2.08 ±0.59, respectively, all P 〈 0.01）. CONCLUSION： High fat dietinduced obesity is associated with elevated intestinal maltase activity, GLUT2 expression, and permanent apical GLUT2 in the small intestinal mucosa of rats. Octreotide can inhibit these effects.

Epidermal growth factor upregulates serotonin transporter and its association with visceral hypersensitivity in irritable bowel syndrome

AIM: To investigate the role of epidermal growth factor (EGF) in visceral hypersensitivity and its effect on the serotonin transporter (SERT).

The Absorption and Transportation of Glutamine Containing Small Peptides-Arg-Gly-GIn and Gly-GIn in Jejunum of Weaned Piglets

In order to research the absorption and transportation differences ofglutamine containing small peptides and free glutamine in intestine of weaned piglets, 28-day-old weaned piglets were selected to get the sample for jejunum culture in vitro in this study. Trial 1 was conducted to study the stability of tripeptide （Arg-Gly-Gln） in the jejunum to determine the ideal culture time. It was designed into 2 treatments： control group （Kreb＇s solution, GC） and tripeptide group （by adding 556μmol/L of Arg-Gly-Gln to Kreb＇s solution, GP）. They were cultured for 60 min. The absorption and transportation differences ofglutamine existing as Arg-Gly-Gln, Gly-Gln and free Gin were studied in trial 2. It was designed into 4 treatments： group 1 （G1, control group）, Kreb＇s solution; Group 2 （G2）, Kreb＇s solution＋556 μmol/L Arg-Gly-Gln; group 3 （G3）, Kreb＇s solution＋556 μmol/L Gly-Gln and Arg; group 4 （G4）, Kreb＇s solution＋556 μmol/L arginine, glycine and glutamine. They were cultured for 40 minutes. The results indicated that the absorption and transportation of glutamine existing as Arg-Gly-Gln was more efficient than those of Gly-Gln while Gly-Gln was more efficient than free glutamine. Arg-Gly-Gln may be more excellent than Gly-Gln in physiological functions and nutrition potential.

Photothermal‐boosted polaron transport in Fe_(2)O_(3)photoanodes for efficient photoelectrochemical water splitting

Introduction of the photothermal effect into transition-metal oxide photoanodes has been proven to be an effective method to improve the photoelectrochemical(PEC)water-splitting performance.However,the precise role of the photothermal effect on the PEC performance of photoanodes is still not well understood.Herein,spinel-structured ZnFe_(2)O_(4)nanoparticles are deposited on the surface of hematite(Fe_(2)O_(3)),and the ZnFe_(2)O_(4)/Fe_(2)O_(3)photoanode achieves a high photocurrent density of 3.17 mA cm^(-2)at 1.23 V versus a reversible hydrogen electrode(VRHE)due to the photothermal effect of ZnFe_(2)O_(4).Considering that the hopping of electron small polarons induced by oxygen vacancies is thermally activated,we clarify that the main reason for the enhanced PEC performance via the photothermal effect is the promoted mobility of electron small polarons that are bound to positively charged oxygen vacancies.Under the synergistic effect of oxygen vacancies and the photothermal effect,the electron conductivity and PEC performance are significantly improved,which provide fundamental insights into the impact of the photothermal effect on the PEC performance of small polaron-type semiconductor photoanodes.

Multiple methoxy-substituted hole transporter for inverted perovskite solar cells

Inverted organic-inorganic hybrid perovskite solar cells(i-PSC)with low temperature processed interlayers and weak hysteresis behaviors have shown great potential for commercialization[1-5].However,their relatively lower power conversion efficiency(PCE)and inferior reproducibility than conventional PSCs limit further developments.These problems are largely determined by the hole transporting layer(HTL)and the quality of the upper perovskite film[6-8];in particular,the latter is considerably influenced by the surface property of the underlying HTL.

The Physiological Model of Na⁺-Dependent Transporters for Glucose and Amino Acids in Rat and Turtle

Conditions in rat and turtle small intestine tissue where glucose and glycine transport is inhibited while glucose-induced Na+ transport is preserved are described. The generally accepted model for the Na+-dependent transporter (а single channel for the Na+ and nutrient) does not account for the data obtained from the analysis of the interaction between the transport of glucose, glycine, and Na+ at different temperatures and the effect of inhibitors оn these рroсеssеs. The phenomenon of temperature uncoupling of Na+ and nutrient transport саn best bе described bу а two-pathway model with а gate mechanism. According to this model, the Na+-dependent transporter has at least two pathways: оnе for Na+ and another for nutrients. The model рrovidеs for the passage of Na+ in both directions along а channel opened bу glucose. Experiments are carried out using the addition of glucose and glycine on backgrounds of glycine and glucose, respectively. It has been hypothesized that when all three transporters (for Na+, glucose and glycine) are unite in a single structure, then there should be “competitive relations” between short-circuit current changes on glycine and glucose for sodium ions passing through its transporter.

A Study on Description Methods of Sediment Transport Modulus in Small Watersheds

[Objective]This study aimed to clear the advantages,disadvantages and applicability of various analysis methods to assess sediment transport modulus in small watersheds using the multi-year observation data. [Method]Four methods,including the statistical eigenvalues,depolarized arithmetic mean,frequency of erosion intensity and box-whisker plots were applied into calculation of sediment transport modulus in four small watersheds,and then the results of the methods were compared to to filter a method with the widest applicability and scientific validity. [Result] The statistical arithmetic mean and median could hardly represent the concentration and general level of multi-year sediment transport modulus. Although the depolarized arithmetic mean had the tendency of reflecting the general level of data,it lost the extreme value and its information for making decision. The frequency of erosion intensity grade reflected the distribution of data in intensity classification. Box-whisker plot could show the concentration,dispersion and the number of abnormal data. [Conclusion] Multiple methods can be combined to comprehensively and objectively characterize the multi-year sand transport modulus due to their advantages and disadvantages. Additionally,box-whisker plot has good objectivity and applicability in displaying the multi-year data of small watershed.

国际可移动小型堆开发与运输安全研究现状

可移动小型堆(TNPPS)作为小型模块化反应堆(SMR)的一种(一般指30 MW以下的SMR),当通过陆路、海运等方式运输后在运输工具上或者从运输工具卸载后能够运行和产生电能,可以满足偏远、局部区域的供热、用电需求,引起了各国的重视。本文简要介绍了国际可移动小型堆发展现状,重点对国际上不同类型可移动小型堆的特点、可移动小型堆发展面临的问题和挑战进行总结,并重点讨论了可移动小型堆运输安全相关问题及对策建议。

无人机高空航拍视角下小尺度车辆精确检测方法

无人机高空航拍图像中车辆像素占比极低,目标可视化信息较少,在目标检测任务中容易漏检和误检。因此,本文提出一种基于改进YOLOX(You Only Look Once X)的无人机高空航拍视角下小尺度车辆精确检测方法。首先,为增强网络对低级特征的提取能力,在原始YOLOX预测头部增加一个160 pixel×160 pixel的浅层特征提取网络;其次,在骨干网络后端嵌入基于归一化的注意力机制模块(Normalization-based Attention Module,NAM),以抑制冗余的非显著特征表达;最后,为了增大小尺度车辆的相对像素比,提升网络捕捉有效特征信息的能力,提出一种基于滑动窗口的图像切分检测方法。试验结果表明,改进YOLOX网络表现出良好的检测效能,检测精度达到了84.58%,优于典型的目标检测网络Faster R-CNN(79.95%)、YOLOv3(83.69%)、YOLOv5(84.31%)及YOLOX(83.10%)。此外,改进YOLOX能够有效解决无人机高空航拍图像中小尺度车辆的漏检和误检问题,且预测框更贴合车辆的实际轮廓;同时,在不同航拍高度的目标检测任务中具有较高的鲁棒性。

基于CCR模型的中小城市公交运行效率评价方法

为了缓解资源的有限性和城市公交服务日益增长需求对公交系统运营和发展带来的压力,提高公交线路运行效率,构建以线路长度、重复系数、非直线系数、站点覆盖率、站点数量和线网密度为投入指标,线路可达性和行车准点率为产出指标的评价指标体系,采用数据包络分析法中的CCR模型对公交线路运行效率进行评价。以本溪市主城区16条公交线路运营情况为例,进行有效性分析。分析结果表明:1路、9路、25路、26路、32路、33路综合效益值均小于1,线路运行效率仍有待提升,其中线路长度、站点数量两个指标影响程度较高,可基于实际情况对该指标进行优化,提高线路运行效率。研究成果可为本溪市公交发展与城乡规划提供参考依据,也可为中小城市公交线路运行效率评价提供新的思路。

大吨位箱梁曲线段梁上运梁承压箱梁受力分析

研究目的:杭甬高速复线宁波段一期工程S1标段采用大吨位预应力混凝土箱梁(50 m/1650 t),使用YL1800型运梁车采用单车跨双幅梁上运梁方案,为研究大吨位箱梁在小半径曲线段(R=1800 m)进行梁上运梁时下部承压箱梁的受力性能,验证运梁方案的可行性,对下部承压箱梁进行了测试与分析。研究结论:(1)大吨位箱梁在梁上运梁过程中,承压箱梁跨中截面顶板、底板沿纵向均处于受压状态,顶板沿横向处于受压状态,箱梁的受力满足规范要求;(2)随着运梁车偏载距离的增大,承压箱梁的应力和跨中挠度逐渐增大,运梁车向低侧偏载时对箱梁应力和跨中挠度影响较大,建议在梁上运梁时运梁车向高低两侧偏载不应超过1000 mm;(3)本研究成果可为大吨位箱梁梁上运梁施工提供参考。

我国空间推进技术领域发展思考与建议

我国空间推进技术领域历经60余年发展形成了较完善的技术体系和较丰富的产品谱系,支持了载人航天、应用卫星、深空探测等重大工程应用;面向我国航天领域未来规划、重大工程和科学项目的应用需求,空间推进系统现有的技术水平存在不足,亟需谋划创新发展和突破方向。本文从电推进、化学推进、核推进、新概念空间推进等角度出发,系统梳理了空间推进系统的发展现状;重点提炼了高性能、低成本的空间推进系统支撑低轨小卫星组网发展,大推力、可重复使用的低温化学推进技术推动新型空间运输系统发展,多类型、长寿命的空间推进技术保障深空关键应用等未来应用需求。研究认为,我国空间推进技术领域面临系统可靠性和寿命亟需进一步提高、部分领域的产品成熟度与国际先进水平差距明显、产品成本高、可选推进技术种类少且重点技术研究滞后等迫切挑战,需开展顶层规划、优化技术选择,重视基础研究、构建发展机制,在重点技术方向上分类推进科研攻关,尽快实现低轨小卫星、地月空间转移、深空探测(含载人航天)用推进系统的技术突破与在轨应用。

施氮量与移栽密度对小粒型杂交水稻产量形成的影响

【目的】明确小粒型杂交稻的产量形成特性。【方法】以卓两优0985(小粒型杂交稻)和丰两优4号(对照)为材料,在不同施氮量(0,N0;180 kg/hm^(2),N1;210 kg/hm^(2),N2)和密度(26.7 cm×20.0 cm,D1;20.0 cm×20.0 cm,D2;20.0 cm×16.7 cm,D3)条件下开展大田试验。【结果】两品种LAI、叶片SPAD值随施氮量增大而提高,N1与N2差异不显著,但显著高于N0处理;两品种茎鞘物质输出率随施氮量增大而下降,而叶片物质输出率表现相反;两品种产量随施氮量增加而提高,但N1与N2间差异不显著,不同密度处理下一般以D2处理较高;N0处理下卓两优0985产量显著高于对照品种,而施氮条件下两品种产量相当。【结论】卓两优0985产量形成特性为叶面积较小、穗粒数较多、库源比较大,灌浆中后期光合优势明显,花后物质积累量与茎叶物质转运率、经济系数较高,不施氮条件下具有较高产量等。本研究条件下,卓两优0985以N1D2(180 kg/hm^(2)、20 cm×20 cm)为最佳处理。

基于改进WGAN考虑特征分布相似性的小样本负荷预测方法

对于综合能源系统中新接入用户,其往往由于历史数据匮乏而难以建立精准的短期负荷预测模型.本文基于迁移学习理论,提出了一种基于改进Wasserstein生成对抗网络(WGAN)的小样本负荷预测方法.首先,本文采用最大信息系数法量化各影响特征与负荷的相关性强弱.接着,将源域特征序列进行分割,计算各分割子序列与目标域小样本的实序列编辑距离确定初始源域.然后,引入卷积神经网络和长短期记忆模型建立源域预测网络.通过WGAN对齐目标域和源域负荷特征的空间分布,并在最优传输代价函数中加入局部特征损失以提高训练的稳定性和快速性.最后,将对抗训练后网络用于目标域负荷预测.采用该方法对某地区小样本负荷进行实验,结果表明,本文所提算法与其他预测模型相比能达到更高精度.

长轨运输车极小半径曲线运行安全性分析

长轨运输车运载长钢轨通过半径R为65 m的极小半径曲线段时,由于曲线半径极小和长钢轨通过曲线段时对车辆产生支反力的共同影响,车辆的运行安全性差。为确保所设计的长轨运输车能安全通过该曲线段进行轨道作业时,首先对长轨运输车的曲线通过能力进行理论分析,然后计算所运载的长钢轨对车辆产生的支反力,建立长轨运输车动力学仿真模型,计算长轨运输车空载、重载低速动态通过曲线段的运行安全性指标,并叠加支反力后依据《铁道特种车辆和轨行机械动力学性能评定及试验方法》(GB/T 17426—1998)进行安全性评定,最后通过实车试验验证理论计算和仿真分析。结果表明:所设计的长轨运输车有通过R65 m极小半径曲线段的能力,其重载工况动态通过该曲线段时的极限速度高于空载工况,且长轨运输车空载、重载以5~15 km/h速度动态通该曲线段时运行安全性能良好,具有一定的安全裕值,满足实际轨道作业的速度需要。

活饵与饲料投喂对幼鳜肠肽酶活力及小肽转运、吸收的影响

以初始体重(6.77±0.64)g的鳜(Siniperca chuatsi)为实验对象,从消化道肠肽酶活力和小肽转运吸收方面比较研究鳜对活饵与饲料消化吸收能力的差异。实验采用3种分组投食策略,将鳜分活饵组(仅投喂活饵鱼)、饲料组(仅投喂饲料)、复投活饵组(以下简称复投组,先投喂饲料后活饵鱼)。活饵组、饲料组分别饲养22d,复投组经5d驯饲、15d饲料和2d活饵喂养。饲养结束时在各组进食0.5h、1h、2h、3h、6h、12h、16h时分别取样肠和幽门盲囊,测定氨肽酶和羧肽酶含量与活力,小肽转运载体基因Pept1a、Pept1b和Pept2 mRNA表达水平,及进食12h后肠内容物及粪便中残余小肽含量。结果表明:各组羧肽酶、氨肽酶含量变化无显著性规律,酶活力总体呈先升后降趋势;活饵组肽酶活力峰值显著高于复投组高于饲料组(P<0.01),复投组由饲料转喂活饵后,肠道肠肽酶活力显著上升;各组前肠、中肠及幽门盲囊Pept1a、Pept1b mRNA表达显著高于后肠(P<0.01),后肠则以Pept2 mRNA高表达(P<0.01)。在复投组摄食活饵后,小肽转运载体基因表达水平较饲料组迅速回升(P<0.01);摄食12h,复投组肠内容物小肽含量显著高于活饵组和饲料组,小肽吸收效率随消化时间延长而上升。饲料组粪便中小肽含量显著高于活饵组与复投组,未转运的小肽中含必需氨基酸居高。综上所述,投喂鳜配合饲料,对肠肽酶活力、小肽转运载体基因表达和小肽吸收速率均产生不利影响,鳜对饲料蛋白的分解和小肽转运吸收效率显著低于活饵鱼。

高速公路互通立交小半径匝道车辆行驶轨迹特征分析

为明确高速公路互通立交小半径匝道的车辆行驶轨迹特征和驾驶模式,使用无人机在四川省2处高速公路互通立交上空进行高空拍摄,利用视频分析方法采集了小半径匝道上汽车行驶的轨迹数据、速度及行驶轨迹坐标等。通过分析行驶轨迹与车道线的占用关系,得到了不同车型轨迹与不同行驶阶段之间的关系,明确了不同小半径匝道下的行驶轨迹偏好,并分析了运行速度对不同类型车辆行驶轨迹的影响。采用三点定位法计算得到轨迹曲率,分析了小半径匝道的曲率特征,确定了轨迹曲率与匝道曲率之间的差异及其轨迹横摆特点。结果表明:匝道行驶的车辆中,小客车在小半径匝道缓和曲线段的轨迹线束宽幅宽于重型汽车,在圆曲线段对车道线的侵占较为明显;将行驶过程中车辆的驾驶偏好分为3类,A型喇叭口外环匝道上外侧压弯的小客车和重型汽车运行速度较高,对角象限双环式匝道上内侧切弯的小客车和正常行驶的重型汽车运行速度较高;小客车和重型货车在2种小半径匝道上的轨迹曲率整体大于道路设计曲率,对角象限双环式匝道上车辆轨迹改变的幅度和频率较高。