木片筛余物高得率半化学法清洁制浆技术研究

以太阳纸业备料车间木片筛选碎料（筛余物）为原料，对其烧碱法半化学制浆的实验室工艺和生产试验进行了研究。结果表明，筛余物采用半化学法制浆可获得较高得率和环压强度的纸浆，且用碱量对纸浆性能有显著影响。相对8%NaOH （相对于绝干原料）化学预处理，采用14%NaOH化学预处理结合两段浆浓22%的高浓磨浆工艺，所制半化学浆抄造浆张的裂断长和环压指数分别达2.89 km和9.76 N·m/g，是前者的1.9倍和1.2倍，而且优于现用国内OCC废纸浆抄造浆张；生产试验得到的浆张性能指标与实验室相吻合，其中紧度和环压强度分别达到GB/T 13023—2008瓦楞芯（原）纸AA级和A级优等品要求。     

碳纤维布约束下水泥砂浆动态力学及能量特征EI北大核心CSCD

为研究碳纤维复合材料(CFRP)对水泥砂浆的加固效果,针对普通水泥砂浆和CFRP布端面约束水泥砂浆,采用分离式霍普金森压杆(SHPB)分别进行恒定气压(0.3 MPa)和递增气压(0.2、0.3、0.4、0.5 MPa)循环冲击压缩试验,分析了试件的应力-应变曲线、破坏形态和能量特征.结果表明:与普通水泥砂浆试件相比,CFRP布端面约束水泥砂浆试件的循环冲击次数、峰值应力和峰值应变均有显著提高,且其峰值应力随着应变率的提高而增大;CFRP布的断裂部位主要发生在碳纤维横向连接处,CFRP布减缓了试件内部裂缝的产生,提高了试件的延性,表现出更好的抗冲击能力,试件的残余强度增加;端面粘贴CFRP布可以提高水泥砂浆的能量吸收能力,在相同冲击气压作用下,CFRP布端面约束水泥砂浆产生裂纹所需的能量高于普通水泥砂浆.     

严寒地区室内多层贯通空间热湿环境实测研究

通过对严寒地区贯通空间温湿度在水平方向及垂直方向上的连续实测，分析了供暖前后，太阳辐射、建筑开口、供暖等因素对贯通空间热湿环境的影响有很大差异。结果表明供暖前贯通空间受到太阳辐射、建筑开口的影响较大，温湿度波动明显；供暖期间受供暖因素影响，温差波动不稳定但幅度小。水平方向上非供暖期最大温差为2℃，供暖期最大温差为8℃；垂直方向上非供暖期的最大温差为3℃，供暖期最大温差为7℃。     

Co?N graphene encapsulated cobalt catalyst for H2O2 decomposition under acidic conditions

Hydrogen peroxide (H₂O₂) has been listed as one of the 100 most important chemicals in the world. However, huge amount of residual H₂O₂ is hard to timely decomposed into O₂ and H₂O under acidic condition, easily resulting in explosion hazard. Here, we reported a core–shell structure catalyst, that is graphene with Co N structure encapsulated Co nanoparticles. Co N graphene shell serves as the active site for the H₂O₂ decomposition, and Co core further enhance this decomposition. Benefiting from it, the H₂O₂ decomposition were close to 100% after 6 cycles without pH adjustment, which increased 6 orders of magnitude compared with no catalyst. At the same time, the O₂ generation reached 99.67% in 2 h with little metal leaching, and ·OH has been greatly inhibited to only 0.08%. This work can cleanly remove H₂O₂ with little deep oxidation and protect the process of H₂O₂ utilization to achieve a safer world.     

枪管结构对固有频率的影响

为了研究枪管结构对枪管固有频率的影响,针对枪管尤其是狙击枪管设计中约束长度、枪管外形、膛口装置以及膛线等不同结构,建立了相应的三维模型。采用以六面体为主的网格对枪管进行了网格划分,采用有限元方法对枪管进行了模态分析。计算获得了不同结构枪管的固有频率; 通过比较,得到了不同枪管结构对固有频率的影响。分析结果表明:枪管尾部螺纹长度越长,枪口振动幅度越低; 相同质量枪管,锥形外形枪管刚度最好; 加装膛口装置对枪管刚度和振动特性有不利影响。     

Electrostatic-lenses position-sensitive TOF MCP detector for beam diagnostics and new scheme for mass measurements at HIAF

A foil–microchannel plate(MCP) detector,which uses electrostatic lenses and possesses both good position and timing resolutions, has been designed and simulated for beam diagnostics and mass measurements at the next-generation heavy-ion-beam facility HIAF in China. Characterized by low energy loss and good performances of timing and position measurements, it would be located at focal planes in fragment separator HFRS for position monitoring, beam turning, Bρ measurement, and trajectory reconstruction. Moreover, it will benefit the building-up of a magnetic-rigidity–energy-loss–time-offlight(Bρ-△E-TOF) method at HFRS for high-precision in-flight particle identification of radioactive isotope beams on an event-by-event basis. Most importantly, the detector can be utilized for in-ring TOF and position measurements,beam-line TOF measurements at two achromatic foci, and position measurements at a dispersive focus of HFRS, thus making it possible to use two complementary mass measurement methods [isochronous mass spectrometry at the storage ring SRing and magnetic-rigidity–time-of-flight(Bρ-TOF) at the beam-line HFRS] in one single experimental run.     

Ms以下温度等温淬火对中碳贝氏体钢相变和性能影响

摘要：设计了马氏体起始相变温度（Ms）以上和以下2个不同温度等温淬火试验，结合热膨胀仪、扫描电镜显微组织、X光衍射和拉伸试验等试验手段，研究了对比于Ms以上温度等温淬火试验，Ms以下等温淬火对中碳贝氏体钢相变、组织和性能的影响。结果表明，贝氏体相变可以发生在Ms温度以下，且其相变动力学被明显促进。相比于Ms以上温度等温淬火，Ms温度以下等温淬火虽然可以加速相变动力学，但导致强度和伸长率下降，因此降低了最终的力学性能。这主要是因为Ms温度以下等温淬火试样组织内部出现了大量的回火无热马氏体（AM）和少量的贝氏体和残余奥氏体（RA）。因此，Ms温度以下等温淬火热处理后的组织性能未必优于Ms温度以上等温处理后组织性能，这主要取决于具体的成分和工艺。     

Weighted power means of q-rung orthopair fuzzy information and their applications in multiattribute decision making

Weighted power means with weights and exponents serving as their parameters are generalizations of arithmetic means. Taking into account decision makers' flexibility in decision making, each attribute value is usually expressed by a $q$-rung orthopair fuzzy value ($q$-ROFV, $q\ge 1$), where the former indicates the support for membership, the latter support against membership, and the sum of their $q$th powers is bounded by one. In this paper, we propose the weighted power means of $q$-rung orthopair fuzzy values to enrich and flourish aggregations on $q$-ROFVs. First, the $q$-rung orthopair fuzzy weighted power mean operator is presented, and its boundedness is precisely characterized in terms of the power exponent. Then, the $q$-rung orthopair fuzzy ordered weighted power mean operator is introduced, and some of its fundamental properties are investigated in detail. Finally, a novel multiattribute decision making method is explored based on developed operators under the $q$-rung orthopair fuzzy environment. A numerical example is given to illustrate the feasibility and validity of the proposed approach, and it is shown that the power exponent is an index suggesting the degree of the optimism of decision makers.     

Enhanced Sensitivity in Nanopore Sensing of Cancer Biomarkers in Human Blood via Click Chemistry

Cancer biomarkers are expected to be indicative of the occurrence of certain cancer diseases before the tumors form and metastasize. However, many biomarkers can only be acquired in extremely low concentrations, which are often beyond the limit of detection (LOD) of current instruments and technologies. A practical strategy for nanopore sensing of cancer biomarkers in raw human blood down to the femtomolar level is developed here. This strategy first converts the detection of cancer biomarkers to the quantification of copper ions by conducting a sandwich assay involving copper oxide nanoparticles. The released Cu²⁺ is then taken to catalyze the “click” reaction which ligates a host–guest modified DNA probe. Finally, this DNA probe is subjected to single‐channel recordings to afford the translocation events that can be used to derive the concentrations of the original biomarkers. Due to the amplification effects of nanoparticle loadings and the “click” reaction, the LOD of this strategy can be as low as the subfemtomolar level. Further, the acid treatment step could effectively eliminate the interferences from plasma proteins in raw human blood and make the strategy highly suitable for the detection of cancer biomarkers in clinical samples.