Fabrication and Characterization of Highly Oriented Composite Nanofibers with Excellent Mechanical Strength and Thermal Stability

Here, highly‐oriented poly(m‐phenylene isophthalamide)/polyacrylonitrile multi‐walled carbon nanotube (PMIA/PAN‐MWCNT) composite nanofiber membranes with excellent mechanical strength and thermal stability are successfully produced using electrospinning. It is demonstrated that the cooperation of multi‐walled carbon nanotubes (MWCNT) and high‐speed rotating collection is beneficial to the acquisition of highly oriented fibers and effectively improves the mechanical strength of the membrane along the orientation direction. Specifically, the tensile stress of poly(m‐phenylene isophthalamide)/polyacrylonitrile (PMIA/PAN) membrane is enhanced significantly from 10.6 to 20.7 MPa, benefiting from the highly oriented alignment of the fibers as well as the reinforcing effect of MWCNTs on the fibers. Furthermore, the stressing process of single fiber and fiber aggregates is carefully simulated, and the influence of MWCNTs on the mechanical properties of PMIA/PAN‐MWCNT membranes is analyzed comprehensively, providing a meaningful auxiliary means for the study of mechanical properties. In addition, the composite nanofiber membrane has the advantages of both PMIA and PAN, possessing high temperature resistance, flame‐retardancy, and chemical stability, for an ideal high‐temperature material. In short, the as‐prepared PMIA/PAN‐MWCNT composite membrane with excellent comprehensive property emerges a promising application in many fields, especially in high‐tech.     

电液控制系统关键传感器的故障预警方法研究

为了保证电液控制系统的正常运行,对电液控制系统核心传感器部件的故障预警是关键一环,分析了传感器在电液控制系统的工作原理,得到了传感器在系统中的故障规律,为了对井下的电液控制系统中的核心传感器的故障进行预警和诊断,结合目前比较流行的传感器故障预警方法,以液压支架的压力传感器为例,提出了一个静态分析与动态分析融合的诊断方法,其核心是通过对传感器采集的数据进行分析,能有效预测压力传感器故障,提高电液控制系统的可靠性。     

Small-Molecule Inhibitors of METTL3, the Major Human Epitranscriptomic Writer

The RNA methylase METTL3 catalyzes the transfer of a methyl group from the cofactor S-adenosyl-L-methionine (SAM) to the N⁶ atom of adenine. We have screened a library of 4000 analogues and derivatives of the adenosine moiety of SAM by high-throughput docking into METTL3. Two series of adenine derivatives were identified in silico, and the binding mode of six of the predicted inhibitors was validated by protein crystallography. Two compounds, one for each series, show good ligand efficiency. We propose a route for their further development into potent and selective inhibitors of METTL3.     

Preclinical Evaluation of 99mTc-ZHER2:41071, a Second-Generation Affibody-Based HER2-Visualizing Imaging Probe with a Low Renal Uptake

Radionuclide imaging of HER2 expression in tumours may enable stratification of patients with breast, ovarian, and gastroesophageal cancers for HER2-targeting therapies. A first-generation HER2-binding affibody molecule [^99mTc]Tc-ZHER2:V2 demonstrated favorable imaging properties in preclinical studies. Thereafter, the affibody scaffold has been extensively modified, which increased its melting point, improved storage stability, and increased hydrophilicity of the surface. In this study, a second-generation affibody molecule (designated ZHER2:41071) with a new improved scaffold has been prepared and characterized. HER2-binding, biodistribution, and tumour-targeting properties of [^99mTc]Tc-labelled ZHER2:41071 were investigated. These properties were compared with properties of the first-generation affibody molecules, [^99mTc]Tc-ZHER2:V2 and [^99mTc]Tc-ZHER2:2395. [^99mTc]Tc-ZHER2:41071 bound specifically to HER2 expressing cells with an affinity of 58 ± 2 pM. The renal uptake for [^99mTc]Tc-ZHER2:41071 and [^99mTc]Tc-ZHER2:V2 was 25–30 fold lower when compared with [^99mTc]Tc-ZHER2:2395. The uptake in tumour and kidney for [^99mTc]Tc-ZHER2:41071 and [^99mTc]Tc-ZHER2:V2 in SKOV-3 xenografts was similar. In conclusion, an extensive re-engineering of the scaffold did not compromise imaging properties of the affibody molecule labelled with ^99mTc using a GGGC chelator. The new probe, [^99mTc]Tc-ZHER2:41071 provided the best tumour-to-blood ratio compared to HER2-imaging probes for single photon emission computed tomography (SPECT) described in the literature so far. [^99mTc]Tc-ZHER2:41071 is a promising candidate for further clinical translation studies.     

Evaluation of particle recovery from microalgae

Coccoliths are micro-structured biomineral particles found in cell protective covering layers of coccolithophore species. They are mainly composed of CaCO₃ and their individual crystal entities are arranged in such a way that they construct complex and unique structures. This complexity is found down to the individual particle level and appears to have promising properties to offer. This study focuses on the essential step prior to any kind of implementation, which is the recovery of the material. It summarizes cleaning protocols found in literature, compares them for the first time for the same freshly cultivated material and addresses challenges that still need to be overcome. Further, it highlight the advantages and disadvantages of the best cleaning protocols, suggests optimizations with promising results and uses size distribution measurements to analyse the recovery efficiency. To that end, further characterization techniques, new for coccoliths, are introduced and used to improve our current knowledge of the particles behaviour.     

m采高采煤机牵引箱加载试验分析

为了满足9 m采高特厚煤层综采要求,设计了MG1100/3050-WD采煤机。鉴于新牵引箱的结构和参数,选择了倒置的加载方式。采用液压加载试验台进行热平衡试验,并对试验结果进行了分析,满足空载试验和热平衡试验标准和要求。此牵引箱达到型式试验要求,可以出厂进行工业性试验。     

680m~3浮选机工业化应用过程中的动力学性能测试与分析

680m~3浮选机投入生产试运行已一年有余,表现出卓越的设备稳定性和分选性。本文从浮选流体动力学角度出发,对680m~3浮选机在带矿运行过程中的充气性能、矿浆循环悬浮性能和气泡大小及其负载性能进行了测试分析。结果表明,680m~3浮选机充气量可以达到1.1m~3/(m~2·min)以上,能够满足一般硫化矿大气量的生产需求,空气分散度在7以上,平均气含率约7%;不同深度浮选槽内矿浆浓度和粒级分布较为均匀,无明显分层现象。气泡表面积通量可达39.20s-1,随着气泡的上浮,气泡负载呈现上升趋势,最高可达3.37g/L。优越的浮选流体动力学特性充分地保障了680m3浮选机良好的分选效果。     

0.2 m高分辨率数字聚焦双侧向测井仪发射电路设计

针对0.2m高分辨率数字聚焦双侧向测井仪器的理论条件和工程需要,设计了发射电路,包括信号源与功率控制、基于电流源输出的模式1(35 Hz)和模式3(140 Hz)信号发射、基于电压源输出的模式2(280 Hz)信号发射、辅助监督等单元电路,确保三种模式同时工作、互不干扰以及辅助聚焦,三个模式的信号发射功率能够自动控制。室内测试与现场应用均表明,所设计的发射电路适用于0.2 m高分辨率数字聚焦双侧向测井仪器,测量值准确可靠,能够为油田薄层识别、饱和度求取以及水淹层判别提供准确可靠的高分辨率电阻率测井资料。     

千米深井大倾角煤层综放采场矿压显现实测研究

针对开滦赵各庄矿3237深部大倾角综放工作面的矿压显现和围岩活动规律进行了全面的实测研究,通过多种观测手段和研究方法,获得了大量的观测数据,初步掌握了大采深大倾角厚煤层条件下综放开采工作面矿压显现的基本规律与顶板的运移特征,得出了大采深与大倾角回采巷道变形与支承压力的分布特征.     

煤矿工业电视系统的设计

阐述了煤矿工业电视系统的原理及结构 ,描述了系统各部分的设计及选型 ,尤其是视频传输的光纤部分 ,着重讲解了煤矿工业电视系统的要点 ,指出了施工中应注意的问题。实际运行证明 ,该系统设计合理 ,发挥了其应有的作用