Fire Intumescent,High-Temperature Resistant,Mechanically Flexible Graphene Oxide Network for Exceptional Fire Shielding and Ultra-Fast Fire Warning

Smart fire alarm sensor(FAS)materials with mechanically robust,excellent flame retardancy as well as ultra-sensitive temperature-responsive capability are highly attractive platforms for fire safety application.However,most reported FAS materials can hardly provide sensitive,continuous and reliable alarm signal output due to their undesirable temperature-responsive,flame-resistant and mechanical performances.To overcome these hurdles,herein,we utilize the multi-amino molecule,named HCPA,that can serve as triple-roles including cross-linker,fire retardant and reducing agent for decorating graphene oxide(GO)sheets and obtaining the GO/HCPA hybrid networks.Benefiting from the formation of multi-interactions in hybrid network,the optimized GO/HCPA network exhibits significant increment in mechanical strength,e.g.,tensile strength and toughness increase of~2.3and~5.7 times,respectively,compared to the control one.More importantly,based on P and N doping and promoting thermal reduction effect on GO network,the excellent flame retardancy(withstanding~1200℃flame attack),ultra-fast fire alarm response time(~0.6 s)and ultra-long alarming period(>600 s)are obtained,representing the best comprehensive performance of GO-based FAS counterparts.Furthermore,based on GO/HCPA network,the fireproof coating is constructed and applied in polymer foam and exhibited exceptional fire shielding performance.This work provides a new idea for designing and fabricating desirable FAS materials and fireproof coatings.

Fluid flow characteristics of single inclined circular jet impingement for ultra-fast cooling

The fluid flow characteristics of the single bunch inclined jet impingement were investigated with different jet flow velocities,nozzle diameters,jet angles and jet-to-target distances for ultra-fast cooling technology.The results show that the peak pressure varying significantly from nearly 0.5 to above 13.4 kPa locates at the stagnation point with different jet diameters,and the radius of impact pressure affected zone is small promoted from 46 to 81 mm in transverse direction,and 50 to 91 mm in longitude direction when the jet flow velocity changes from 5 to 20 m/s.However,the fluid flow velocity is relatively smaller near the stagnation point,and increases gradually along the radius outwards,then declines.There is an obvious anisotropic characteristic that the flow velocity component along the jet direction is about twice of the contrary one where the jet anlge is 60°,jet diameter is 5 mm,jet length is 8 mm and jet height is 50 mm.

Case-Based Reasoning(CBR) Model for Ultra-Fast Cooling in Plate Mill

New generation thermo-mechanical control process（TMCP） based on ultra-fast cooling is being widely adopted in plate mill to product high-performance steel material at low cost. Ultra-fast cooling system is complex because of optimizing the temperature control error generated by heat transfer mathematical model and process parameters. In order to simplify the system and improve the temperature control precision in ultra-fast cooling process, several existing models of case-based reasoning（CBR） model are reviewed. Combining with ultra-fast cooling process, a developed R5 CBR model is proposed, which mainly improves the case representation, similarity relation and retrieval module. Certainty factor is defined in semantics memory unit of plate case which provides not only internal data reliability but also product performance reliability. Similarity relation is improved by defined power index similarity membership function. Retrieval process is simplified and retrieval efficiency is improved apparently by windmill retrieval algorithm. The proposed CBR model is used for predicting the case of cooling strategy and its capability is superior to traditional process model. In order to perform comprehensive investigations on ultra-fast cooling process, different steel plates are considered for the experiment. The validation experiment and industrial production of proposed CBR model are carried out, which demonstrated that finish cooling temperature（FCT） error is controlled within±25℃ and quality rate of product is more than 97%. The proposed CBR model can simplify ultra-fast cooling system and give quality performance for steel product.

Thermal conductivity characterization of ultra-thin silicon film using the ultra-fast transient hot strip method

Thermal conductivity is an important material parameter of silicon when studying the performance and reliability of devices or for guiding circuit design when considering heat dissipation, especially when the self-heating effect becomes prominent in ultra-scaled MOSFETs.The cross-plane thermal conductivity of a thin silicon film is lacking due to the difficulty in sensing high thermal conductivity in the vertical direction.In this paper, a feasible method that utilizes an ultra-fast electrical pulse within 20 μs combined with the hot strip technique is adopted.To the best of our knowledge, this is the first work that shows how to extract the cross-plane thermal conductivity of sub-50 nm(30 nm, 17 nm, and 10 nm)silicon films on buried oxide.The ratio of the extracted cross-plane thermal conductivity of the silicon films over the bulk value is only about 6.9%, 4.3%, and 3.8% at 300 K, respectively.As the thickness of the films is smaller than the phonon mean free path, the classical heat transport theory fails to predict the heat dissipation in nanoscale transistors.Thus, in this study, a ballistic model, derived from the heat transport equation based on extended-irreversible-hydrodynamics(EIT), is used for further investigation, and the simulation results exhibit good consistence with the experimental data.The extracted effective thermal data could provide a good reference for precise device simulations and thermoelectric applications.

Ultra-fast x-ray-dynamic experimental subsystem

Ultra-fast x-ray-dynamic experimental subsystem is a facility which can provide femtosecond hard x-ray sources using a femtosecond laser interacting with plasmas. By utilizing these ultra-fast x-rays as a probe, combined with a naturally synchronized driver laser as a pump, we can perform dynamic studies on samples with a femtosecond time resolution. This subsystem with a four-dimensional ultra-high spatiotemporal resolution is a powerful tool for studies of the process of photosynthesis, Auger electron effects, lattice vibrations, etc. Compared with conventional x-ray sources based on accelerators, this table-top laser-driven x-ray source has significant advantages in terms of the source size, pulse duration, brightness, flexibility, and economy. It is an effective supplement to the synchrotron light source in the ultrafast detection regime.

Observations of Microwave Ultra-Fast Absorption Phenomena Above Solar Active Region

While we process observational data of the Flares 22, two rare phenomena of microwave ultra fast absorption (MUFA) are found for the first time. They occurred at 3 67 GHz and 4 00 GHz in the atmospheric layers above both active regions of NOAA/USAF 4808 and 5060 in the interval 05 h50 m17 s～05 h50 m25 s UT on May 19, 1987 and 07 h38 m50 s～07 h38 m58 s UT on June 29, 1988, respectively. These absorption phenomena were observed with Phoenix Ⅱ Micowave Spectrometer at three frequencies (1 42, 2 84 and 3 67 GHz) and (1 42, 2 84 and 4 00 GHz) at Yunnan observatory. Spike emissions appeared at both 2 84 GHz and 1 42 GHz. The notable observational characteristics of both absorption phenomena are given. A possible absorption mechanism of MUFA is discussed.

Ultra-fast charge-discharge and high-energy storage performance realized in K_(0.5)Na_(0.5)NbO_(3)-Bi(Mn_(0.5)Ni_(0.5))O_(3) ceramics

Lead-free relaxor ceramics(1−x)K_(0.5)Na_(0.5)NbO_(3)−xBi(Mn_(0.5)Ni_(0.5))O_(3)((1−x)KNN-xBMN)with considerable charge-discharge characteristics and energy storage properties were prepared by a solid state method.Remarkable,a BMN doping level of 0.04,0.96KNN-0.04BMN ceramic obtained good energy storage performance with acceptable energy storage density Wrec of 1.826 J/cm^(3) and energy storage efficiencyηof 77.4%,as well as good frequency stability(1-500 Hz)and fatigue resistance(1-5000 cycles).Meanwhile,a satisfactory charge-discharge performance with power density PD~98.90 MW/cm^(3),discharge time t0.9<70 ns and temperature stability(30-180°C)was obtained in 0.96KNN-0.04BMN ceramic.The small grain size(~150 nm)and the high polarizability of Bi3+are directly related to its good energy storage capacity.This work proposes a feasible approach for lead-free KNN-based ceramics to achieve high-energy storage and ultra-fast charge-discharge performance as well as candidate materials for the application of advanced high-temperature pulse capacitors.

中型H型钢生产线超快冷技术研究

通过对比国内H型钢超快冷技术的研发情况,结合某公司中型H型钢生产线制约因素及存在的问题,在综合考虑各方面影响因素的基础上,提出超快冷(气雾冷却)工艺的设计方案,旨在利用该技术解决冷床冷却能力不足带来的产品平直度超标、力学性能不稳定、锈蚀严重等问题。

Progress of Radiation Belt Exploration by a Constellation of Small Satellites TGCSS/SGRB, COSPAR

A COnstellation of Radiation BElt Survey(CORBES)program is proposed by the Sub-Group on Radiation Belt(SGRB)of TGCSS,COSPAR.To address the open qustions about the dynamics of the Earth’s radiation belt,CORBES mission would use a constellation of small/CubeSats to take an ultra-fast survey of the Earth’s radiation belt.The concept,science objectives and preliminary technical design of CORBES are introduced.This mission is an international multilateral cooperation mission coordinated by COSPAR.The SGRB Science Activities and COSPAR HQs Coordinate Activities on CORBES are summaried.

超深井工程理论与技术若干研究进展及发展建议

超深井工程受到高温高压、复杂地层、超长井眼和腐蚀介质等多重因素约束,其安全高效作业面临全方位的技术挑战。为此,针对超深井工程的安全高效设计控制问题,介绍了该工程的发展概况与技术特点;选取井眼轨迹预测与防斜打快、钻柱振动特性分析与减振控制、钻井延伸极限预测与设计控制,以及套管失效风险评估与安全控制等几个重要理论与技术问题,介绍了国内外的相关研究进展及笔者团队的最新研究成果;然后,针对超深井工程提出了若干创新发展建议。研究结果表明,超深井工程理论与技术的发展整体呈现出体系化、科学化、多学科交叉、地质与工程一体化等基本特点。建议在基础理论问题、关键核心技术、技术协同关系、技术迭代模式和多学科交叉融合等方面加强创新研究,以持续推进超深井工程基础理论与关键技术创新发展。

应用于人脑胶质淋巴系统的磁共振成像技术研究进展

胶质淋巴系统是神经科学领域近期发现的解剖结构,具有调节间质液运动、废物清除和潜在的大脑免疫等功能,在中枢神经系统的生理及病理中发挥重要作用。随着影像学技术的发展,越来越多的磁共振成像(MRI)技术被应用于人脑胶质淋巴系统的研究,目前常用的MRI技术有动态对比增强磁共振成像技术、沿血管周围间隙扩散张量成像分析技术及新型多模态超快速磁共振技术等,本文就这些技术在脑胶质淋巴系统的应用现状进行汇总综述,以期为胶质淋巴系统的影像学研究提供参考。

经导管二尖瓣缘对缘修复术的超快通道麻醉经验总结

目的回顾性总结超快通道麻醉应用于经导管二尖瓣缘对缘修复术(TEER)治疗功能性二尖瓣反流患者的麻醉方法和围术期麻醉管理经验。方法纳入2022年5—9月在云南省阜外心血管病医院因心力衰竭合并中重度或重度功能性二尖瓣反流行TEER手术,且实施超快通道麻醉的患者。收集患者一般资料、术前合并症、心功能及麻醉分级、术前及术后1年经食管超声心动图检查结果、血清N末端B型脑钠肽前体(NT-proBNP)、手术及拔除气管导管时间、术中麻醉用药、手术及麻醉相关并发症。对麻醉管理、围术期并发症的预防及管理进行分析总结。结果共纳入30例患者,女11例(36.7%),年龄(63.6±6.1)岁。术前纽约心脏病协会(NYHA)心功能分级Ⅳ级14例(46.7%);左心室射血分数(36.0±8.1)%,左心室舒张末期前后径(66.0±8.2)mm;二尖瓣反流程度4+:17例(56.7%),3+:13例(43.3%);NT-proBNP(1934.1±1973.5)pg/ml;采用超快通道麻醉的患者中,有1例(3.3%)患者术中使用大剂量血管活性药。30例患者术后24 h均未发生恶心、呕吐、谵妄、呼吸抑制、围术期经食管超声心动图检查相关消化道大出血、心包积液、脑血管意外、需紧急手术或二次干预及其他术中严重不良事件;无30 d全因死亡发生,平均术后住院(7.4±2.8)d。所有患者完成术后1年随访:左心室射血分数(37.6±11.1)%,左心室舒张末期前后径(63.2±8.6)mm;二尖瓣反流程度2+:7例(23.3%),1+:23例(76.7%);NT-proBNP(1949.2±2576.6)pg/ml。结论超快通道麻醉可应用于TEER治疗功能性二尖瓣反流患者。

基于电子鼻技术的臭灵丹草指纹图谱建立及谱效关系研究

目的:基于超快速气相电子鼻技术,建立15批臭灵丹草饮片的气味指纹图谱,结合谱效相关性分析,筛选与抗氧化活性相关的成分。方法:使用超快速气相电子鼻建立15批臭灵丹草饮片的气味指纹图谱,进行相似度评价。结合AroChemBase数据库进行定性分析。以DPPH自由基、ABTS自由基清除能力为指标评价臭灵丹草饮片挥发性成分的抗氧化活性,结合多元统计分析评价谱效关系,筛选与抗氧化活性关联度较大的成分。结果:建立了15批臭灵丹草饮片的气味指纹图谱,结合AroChemBase数据库标定了14个共有峰,分别为异戊烷、乙叉降冰生烯、α-蒎烯、α-水芹烯、1,8-桉叶素、5-甲基-4-壬烯、柠檬烯、二溴氯丙烷、芳樟醇、甲基丁香酚、十一酸甲酯、β-石竹烯、醋酸十一酯、覆盆子酮。臭灵丹草饮片挥发油清除DPPH、ABTS自由基的IC50分别为6.56~21.26 mg/mL、3.89~18.34 mg/mL,灰色关联度分析及偏最小二乘回归分析结果表明柠檬烯、甲基丁香酚、覆盆子酮等与其抗氧化相关性较大。结论:臭灵丹草饮片超快速气相电子鼻气味指纹图谱结合谱效关系研究初步筛选了与抗氧化能力相关性较大的3个成分,可为臭灵丹草饮片质量控制提供依据。

基于快速气相色谱电子鼻研究超高压射流处理脱脂乳的感官品质

以新鲜脱脂乳为原料,探究超高压射流(ultra-high pressure jet,UHPJ)处理对脱脂乳感官品质的影响。脱脂乳经100~300 MPa UHPJ处理后,采用电子眼、电子鼻、感官评价分别检测脱脂乳颜色、气味及综合风味变化。结果表明:脱脂乳的主要色号以4095白色为主,占比46.80%~53.83%;电子鼻共检测到酯类、酮类、醛类等42种挥发性风味成分,大部分风味成分呈乳香、果香、烘烤香、青草等气味,主成分分析结果显示,300 MPa处理脱脂乳样品和其他样品风味相差较大;感官评价结果显示,UHPJ处理脱脂乳的乳香和甜味较为突出,不同样品之间在甜味、蛋白胨味、铁锈味、烧焦味和寡淡味方面差异明显,250、300 MPa处理样品生成的二甲基硫等硫化物能够显著增强脱脂乳的烧焦味、蛋白胨味。综上,200 MPa UHPJ处理能较完整地保留脱脂乳中的风味成分,进而实现原料乳风味的保持。

实时剪切波弹性成像和彩色脉搏波成像技术评估痛风性关节炎患者颈动脉硬度研究

目的:探讨实时剪切波弹性成像(SWE)和彩色脉搏波成像(UFPWV)技术评估痛风性关节炎(GA)患者颈动脉硬度的应用价值。方法:选择2022年8月至2023年7月期间宜宾市第一人民医院收治的80例GA患者纳入GA组,其中24例经影像学检查确诊合并骨质侵蚀,56例未合并骨质侵蚀;另选取同期在本院进行健康体检的40名健康者纳入健康对照组。采用SWE和UFPWV技术检测所有受检者颈总动脉血管壁杨氏模量最大(Max)、最小(Min)及平均(Mean)值,以及收缩期开始时的脉搏波速度(PWVBS)和收缩期结束时的脉搏波速度(PWVES),评估颈总动脉血管壁纵向和环向血管壁硬度。比较两组杨氏模量值、PWVBS和PWVES差异,分析GA患者合并骨质侵蚀与杨氏模量值、PWVBS和PWVES的相关性。结果:GA组杨氏模量Max值(78.80±12.38)kPa、Min值(57.83±7.42)kPa、Mean值(67.67±8.38)kPa,以及PWVBS(7.06±0.59)m/s和PWVES(9.50±0.63)m/s均显著大于健康对照组,差异有统计学意义(t=11.066、8.216、11.751、14.159、19.118,P<0.05)。合并骨质侵蚀GA患者杨氏模量Max值(82.95±6.37)kPa、Min值(59.59±5.29)kPa、Mean值(72.18±7.62)kPa,以及PWVBS(7.37±0.43)m/s和PWVES(10.43±0.47)m/s均显著大于未合并骨质侵蚀患者[(77.01±5.32)kPa、(57.08±4.73)kPa、(65.73±4.54)kPa和(6.92±0.39)m/s、(9.10±0.41)m/s,t=4.309、2.099、4.699、4.586、12.720,P<0.05]。Spearman相关性分析显示,GA患者杨氏模量Max、Min及Mean值,以及PWVBS和PWVES与合并骨质侵蚀具有显著相关性(r=0.602、0.421、0.682、0.647、0.732,P<0.05)。结论:SWE和UFPWV技术可以评价GA患者血管壁硬度,GA患者颈总动脉血管壁的纵向及环向硬度高于健康人,合并骨质侵蚀的GA患者颈总动脉血管壁的纵向及环向硬度更高。

基于超快速电子鼻对生乳快速鉴别及应用

利用超快速电子鼻检测法快速鉴别不同地区生乳气味信息及异常乳检测应用。收集巴彦淖尔、达拉特旗、林格尔、凉城和宁夏5个地区生乳样品,利用电子鼻对其进行检测,建立指纹图谱,结合保留指数和AroChemBase数据库对生乳样品气味成分进行定性分析,利用主成分分析(PCA)、软独立建模分析(SIMCA)和判别因子分析(DFA)对生乳的香气特征进行分类预测、快速识别。结果表明,不同样品间可以快速区分,5个地区生乳样品在异丙醇和2-丁酮的特征峰面积含量上有主要差异。与生乳相比,异常乳可能的主要差异化合物为乙醇、异戊醛、2-甲基丁醛、2-乙基呋喃和3-甲基-2-丁烯-1-醇,并在异常乳中产生了麦芽味、发酵味、酸味以及油腻味等不良气味。DFA判别因子累计区分指数100%,可以有效区分生乳和异常乳。综上所述,超快速电子鼻能够较好分析生乳气味信息,并快速、有效地鉴别生乳质量。

Effect of Ultra-Fast Cooling on Microstructure of Large Section Bars of Bearing Steel

The ultra-fast cooling technology of large section bars and the microstrueture for different cooling patterns were studied by optical microscope, transmission electron microscope and energy spectrometer. The results indicated that the large section bars were passed through the zone of secondary carbide precipitation quickly by ultra-fast cooling technology （UFC） at instantaneous cooling rate of about 200 ℃/s and the finishing cooling temperature was higher than Ms. The lamellar spacing of pearlite decreased and the microhardness increased with decreasing the rereddening temperature. The precipitation of network carbide was restrained when re-reddening temperature was 690 ℃. And fine laminated pearlite was obtained through transformation of pseudopearlition that induced the reduction of the diameter of pearlite grain and refinement of the lamellar spacing of pearlite, so ideal microstructures of promoting spheroidizing annealing were obtained.

梯度空心玻璃微珠诱导的分形自泵水凝胶的制备及其快速吸水性能研究

通过在水凝胶体系内引入梯度排布的空心玻璃微珠(hollow glass microsphere,HGM),制备了一种具有超高导水效率的分形自泵(fractal self-pumping,FS)水凝胶。在所制备的分形自泵空心玻璃微珠水凝胶(FS-HGM hydrogel)中,水凝胶骨架通过硅烷偶联剂将相邻空心玻璃微珠紧密结合固定,在玻璃微球间形成了逐级变小的亲水分形毛细微通道。结果表明,独特的分形毛细微通道极大地提高了水凝胶的导水性能,在动态接触角实验中表现出超过传统水凝胶约240倍的吸水速率,并且吸水效率随着FS-HGM水凝胶层的增厚有所提升。所制备的快速吸水分形凝胶通过高效移除过量渗出液,加速烫伤伤口愈合,为临床应用中输运生物流体开辟了新途径。

100 kHz弹光调制器多功能调制仿真

针对弹光调制器(photoelastic modulator,PEM)在超高速全偏振领域的测量问题,研究一种目标频率在100 kHz附近的圆型PEM,由弹光晶体和2个方位角相差45°的压电驱动器组成。通过理论计算弹光晶体谐振频率和压电驱动器振动频率,当二者频率达到一致时,PEM工作在谐振状态,此时PEM的调制效率达到最高。当PEM达到谐振状态并趋于稳定后,调节两压电驱动器驱动电压的幅值与相位,实现纯驻波模式和纯行波模式两种特殊调制,纯驻波模式可实现纯电控制下调制快轴的延迟量和方位角;纯行波模式可实现纯电控制下调制快轴以PEM谐振频率的半频速度高速旋转。最后,利用COMSOL有限元仿真模拟两种调制模式下PEM,验证两种调制状态下的PEM振型及其快轴方向,表明PEM可实现多功能弹光调制,为后续偏振测量提供理论支撑。

基于UFLC-QTrap-MS/MS结合多元统计分析的不同产地、不同部位乌药中核苷和氨基酸类成分分析

本研究建立了一种超快速液相色谱-三重四极杆/线性离子阱-串联质谱(UFLC-QTrap-MS/MS)同时测定乌药中11种核苷类和14种氨基酸类成分的分析方法,并结合多元统计分析比较不同产地、不同部位乌药的质量。采用Waters XBridge Amide色谱柱(2.1 mm×100 mm×3.5μm),以0.2%甲酸水溶液(A)-0.2%甲酸乙腈溶液(B)为流动相进行梯度洗脱;在电喷雾正离子模式下,以多反应监测(MRM)进行质谱检测;基于各成分的质量浓度,用方差分析(ANOVA)、主成分分析(PCA)、正交偏最小二乘法判别分析(OPLS-DA)、层次聚类分析(HCA)、逼近理想解排序法(TOPSIS)以及灰色关联度分析(GRA),对不同产地、不同部位乌药样品进行综合评价。结果表明,所测成分在一定浓度范围内具有良好的线性关系,相关系数均大于0.9924;精密度、重复性、稳定性良好,平均加样回收率为94.86%~106.47%,相对标准偏差(RSD)均小于4.55%。不同产地、不同部位乌药样品间存在一定的差异,HCA和PCA 2种方法均将样品分为3类。OPLS-DA模型分析通过VIP值共筛选得到6个差异性化合物,分别为尿苷、丙氨酸、胞嘧啶、黄嘌呤、腺嘌呤、鸟嘌呤。该方法简便、灵敏度高、重现性好,可用于乌药中核苷和氨基酸类成分的同时测定,为药材质量评价和综合利用提供方法参考。