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Experiments looking for rare events like the direct detection of dark matter particles, neutrino interactions or the nuclear double beta decay are operated deep underground to suppress the effect of cosmic rays. But, the production of radioactive isotopes in materials due to previous exposure to cosmic rays is a hazard when ultra-low background conditions are required. In this context, the generation of long-lived products by cosmic nucleons has been studied for many detector media and for other materials commonly used. Here, the main results obtained on the quantification of activation yields on the Earth’s surface will be summarized, considering both measurements and calculations following different approaches. The isotope production cross-sections and the cosmic ray spectrum are the two main ingredients when calculating this cosmogenic activation; the different alternatives for implementing them will be discussed. Activation that can take place deep underground mainly due to cosmic muons will be briefly commented too. Presently, the experimental results for the cosmogenic production of radioisotopes are scarce and discrepancies between different calculations are important in many cases, but the increasing interest on this background source which is becoming more and more relevant can help to change this situation.

Different pretreatment methods for electroless nickel and cobalt plating are demonstrated and compared in the present investigation. The surface morphologies of the nickel or cobalt deposits are investigated by scanning electron microscopy (SEM), and the chemical compositions of the coatings are analyzed by energy-dispersive X-ray spectroscopy (EDX). Method of single-step pretreatment is selected as the optimized method for electroless nickel plating process, while improved two-step sensitization-activation and single-step pretreatment methods can be selected for electroless cobalt plating. It can be found that the content of free Co is much lower compared to electroless Ni plating.

We are concerned with a system of partial differential equations (PDEs) describing internal flows of homogeneous incompressible fluids of Bingham type in which the value of activation (the so-called yield) stress depends on the internal pore pressure governed by an advection–diffusion equation. After providing the physical background of the considered model, paying attention to the assumptions involved in its derivation, we focus on the PDE analysis of the initial and boundary value problems. We give several equivalent descriptions for the considered class of fluids of Bingham type. In particular, we exploit the possibility to write such a response as an implicit tensorial constitutive equation, involving the pore pressure, the deviatoric part of the Cauchy stress and the velocity gradient. Interestingly, this tensorial response can be characterized by two scalar constraints. We employ a similar approach to treat stick-slip boundary conditions. Within such a setting we prove long-time and large-data existence of weak solutions to the evolutionary problem in three dimensions.

Electroless nickel plating is an important process in the fabrication of metal microstructures on silicon substrates. Adhesion of the metal film to the substrate is a key parameter. We report a study of the adhesion of electroless nickel plating on polished silicon for different surface treatments (prior to plating), substrate areas and plating durations. Three different surface treatments considered are: mild etching, palladium activation and nickel activation. Adhesion strength in excess 9.8 × 10⁷N / m² has been obtained. Adhesion requirements for using nickel plating for masking the silicon substrate during anisotropic etching is also discussed.

In this work, a mechanism of catalytic graphitization of D-glucose derived carbon during NaOH activation process is disclosed. The catalytic graphitization is caused by sodium atom, which is produced in the reaction between NaOH and carbon. Due to the combined action of activation and catalytic graphitization resulting from the NaOH, the activated D-glucose derived carbon behaves as a hierarchical micro- and meso-porous structure and has high electrical conductivity. Electrochemical investigations demonstrate that the activated sample exhibits an outstanding rate capability (70% of capacity retention even at a scan rate of 2V s${}^{-1}$) and high specific capacitance (106F g${}^{-1}$) in 6M KOH aqueous electrolyte, which makes it a promising electrode material for high-power supercapacitors.

Hierarchical N-doped carbon nanotubes (NCTs) with controllable aspect ratios were developed for CO₂ adsorption. In this work, NCTs were synthesized by coating different amounts of 3-aminophenol/formaldehyde resin (APF) on the outer layer of silica nanotubes, carbonizing in N₂ at 700^∘C and removing the silica and Ni template by hydrofluoric acid etching. The obtained NCTs were activated by K₂CO₃. After activation, micropores on the activated N-doped carbon nanotubes (ANCTs) were enriched, the micro-surface area and pore volume of ANCT-1.0 reached 1195m²g${}^{-1}$ and 0.45cm³g${}^{-1}$, respectively, and the corresponding adsorption capacity increased by 50% (4.50mmolg${}^{-1}$ at 0^∘C and 1 bar). Moreover, ANCT-1.0 maintained a high stability throughout consecutive adsorption–desorption cycles. The advantages of hierarchical N-doped carbon nanotubes, including their meso–microporous structures, high geometric aspect ratio and good stability, make them valuable and promising materials to capture carbon dioxide.

With the continuous increase in the demand for energy storage equipment, it is imperative to develop new electrode materials with high specific capacitance. In this study, yak dung derived carbon materials (N-YD) were prepared by a simple, economical, and effective method, and it was applied as a supercapacitor electrode material. The N-YD-800 material exhibited high nitrogen content, as well as a large number of multipore structures, which were beneficial to improve the capacitance performance. N-YD-800 exhibited an excellent specific capacitance (346.3Fg${}^{-1}$ at 1Ag${}^{-1})$, good rate performance (56.6% from 0.5Ag${}^{-1}$ to 10Ag${}^{-1})$, and excellent cycling stability (93.3% after 5000 cycles). This study provided a new method for the treatment of livestock and poultry manure resources, affording a cost-effective, easy-to-use carbon source to solve the problem of nonrenewable energy.

How to accelerate the electron transfer to promote the circulating efficiency of Fe${}^{2+}$/Fe${}^{3+}$ is a key problem to be solved, so that magnetic particles can activate peroxymonosulfate well to efficiently degrade acetaminophen (ACE). Herein, a Fe₃O₄@Co₃S₄ catalyst was prepared by modifying Co₃S₄ nanosheets on the surface of magnetic Fe₃O₄ particles. The Co${}^{2+}$ in the modified layer Co₃S₄ accelerates the rate of electron transfer between Fe${}^{2+}$ and Fe${}^{3+}$, thus promoting the circulating efficiency of Fe${}^{2+}$/Fe${}^{3+}$. Fe₃O₄@Co₃S₄/PMS system can degrade over 95% of ACE within 5min. Quenching experiment and ESR tests prove that non-radical ¹O₂ and ${\mathrm{\text{SO}}}_4^{•-}$ played predominant roles in the advanced oxidation process. And after six cycles, the degradation rate could still be higher than 50%.

Apoptosis is an important cellular event that plays a key role in the therapy of many diseases. The mechanism of the initiation and regulation of photodynamic therapy (PDT)–induced apoptosis is complex. Our previous study found that Photofrin was localized primarily in mitochondria, the primary targets of Photofrin-PDT. The key role of Bax in the mitochondria-mediated apoptosis has been demonstrated in many systems. In order to determine the role of Bax in the mitochondrion-mediated apoptosis induced by Photofrin-PDT, we used the GFP-Bax plasmid to monitor the dynamics of Bax activation after PDT treatment. With laser scanning confocal microscopy, we found that Bax did not translocate from the cytosol to mitochondria when the mitochondrial membrane potential (ΔΨm) disappeared, measured by TMRM. Thus, for Photofrin-PDT, the commitment to cell death is independent of Bax activation.

The biomass carbons with highly developed porosity were prepared by carbonization of phoenix tree leaves (PTLs) followed by activation with KOH. The as-prepared carbons possess large interlayer spacing, abundant oxygen-containing functional groups and high degree of structural disorder. The PTLs derived carbons were firstly employed as anodes for sodium-ion batteries, with the optimized material delivering an initial discharge capacity as high as 602mAhg${}^{-1}$ and a reversible capacity of 134mAhg${}^{-1}$ after 300 cycles at 100mAg${}^{-1}$. Electrochemical mechanism analysis reveals a capacitive dominating Na${}^{+}$ storage process.

The advanced oxidation processes (AOPs) based on sulfate radicals have triggered tremendous research efforts in environmental remediation field. In this study, we proposed a facile silver ferrite (${\text{AgFeO}}_2)$ nanocatalyst via a simple co-precipitation at room temperature. The as-prepared AgFeO₂ was characterized by XRD, SEM, TEM, XPS, FTIR and N₂ adsorption–desorption techniques and was used for persulfate (PDS) activation for the first time. The result showed that AgFeO₂ as a PDS activator exhibited superior degradation efficiency of Rhodamine B (RhB) as compared to bare Ag₂O, FeOOH and CuFeO₂. Moreover, the AgFeO₂ catalyst also demonstrated high degradation efficiency for 4-nitrophenol and Methyl Orange in the presence of PDS. The catalytic performance of AgFeO₂ was further evaluated in terms of various parameters, including solution pH, PDS concentration and catalyst dosage. The degradation pathway was proposed based on Liquid Chromatography Mass Spectrometer (LC-MS) result and the degradation mechanism was elucidated through radical scavenger experiments. These findings will extend the scope of novel catalysts for PDS activation and promote the use of AgFeO₂ in more practical applications.

In this work, we activate metal-organic frameworks (MOFs) by applying the general vacuum heating (VH) method or the solvent exchange (SE) method, and encapsulate PSt into the MOF channels by the in-situ polymerization. For the SE method, methanol is optimal to exchange the DMF molecules inside MOF. The effectiveness of these two activation methods is compared. The results show that the MOF activated via the SE method has a higher specific surface area and a larger pore volume than the MOF activated via the general VH method. Also, the SE method is more efficient for the removal of DMF from the MOF channels, and leaves more open metal sites. Specifically, the amounts of loaded monomers inside the MOF activated via the SE method and the general VH method are 4.58 and 2.67 mmol/cm³. Furthermore, the MOF activated via the SE method has better retention of the channel structure and more free volume in the channels. This can increase the mobility of the monomers. As a consequence, the conversion rate of 47.57% from St to PSt is achieved in the MOF activated via the SE method, which is 50.21% higher than that obtained via the general VH method.

The biomass carbons with highly developed porosity were prepared by carbonization of phoenix tree leaves (PTLs) followed by activation with KOH. The as-prepared carbons possess large interlayer spacing, abundant oxygen-containing functional groups and high degree of structural disorder. The PTLs derived carbons were firstly employed as anodes for sodium-ion batteries, with the optimized material delivering an initial discharge capacity as high as 602 mAh g^–1 and a reversible capacity of 134 mAh g^–1 after 300 cycles at 100 mA g^–1. Electrochemical mechanism analysis reveals a capacitive dominating Na⁺ storage process.

Using an activation calculation code FDKR and its associated data library AF-DCDLIB to calculate the radioactivity, decay heat, waste disposal rating and biological hazard potential from activation products, actinides and fission products in the FEB-E. The codes and libraries used in calculation are introduced briefly, and calculation results and decay curves of related hazards after the shutdown of one-year operation of the FEB-E are given. Results obtained show that the total radioactivity inventory, decay heat and BHP at shutdown are 5.74 × 10¹³MBq, 8.34MW and 4.08 × 10⁸km³ of air for 316SS structure material, respectively.

A prerequisite for a synthetic description of the learning and memory (LM), neural bases is a model of the brain. The model we have adopted is based on functional anatomy and consists of three interacting systems. The first, R for representation, is made of the neurons which code sensory information or motor programs with the highest precision. The second, A for activation, comprises the neurons which are most directly involved in arousal and motivation. The third system, S for supervision, controls goal-directed behaviors. The best illustration of its functions is the “voluntary act” in humans: it involves a representation of a goal and of the appropriate strategies, the evaluation of the results and the correction of errors.

The memory system is not an anatomically separate entity but a set of interactions between R, A and S. In these interactions, the three systems have different though complementary functions. R is mainly involved in encoding and storage. S plays a role in encoding and retrieval through the control of attention and cognitive strategies. Structures of A, which modulate R and S activities, are involved in all stages of memory processes. Different types of LM set into play different types of interactions between R, A and S.

Within this general scheme, we considered data from different levels of organization, from the whole brain to the molecule, through intermediates such as small networks (for example, the cortical column). Finally, an attempt is made at defining the perspectives for future research. Among its main objectives are the integration of LM bases in the neurobiology of the whole behavior, the genetic and developmental factors, new therapies for improving memory in aged and demented people, the design of formalisms able to represent large-scale neural networks.