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1.
The one‐electron oxidations of a Fe2 complex lead to the formation of a persistent metal‐stabilized thiyl radical Fe2 species, mixed‐valent Fe4, and Fe8 complexes. The unpaired spin in the Fe2 radical species delocalizes over the Fe2 and the aromatic dithiolate, mostly on the terminal sulfur. The subsequent dimerization of the singly oxidized Fe2 to the Fe4 retains the partial thiyl radical character. For an analogue with less steric hindrance, the π–π stacking interaction between the dithiolato aromatic rings induces generation of the Fe8, in which process electronic structures of the species are modulated through reducing the thiyl radical to the thiolate. Electronic reorganization repeats when the Fe8 is converted to Fe4. Electronic interplay in the complexes decreases the energy gap of frontier MOs and buffers electronic impacts upon redox events. Easier accessible redox potentials and increased stability of the species are facilitated. The results demonstrate that electronic versatility of the benzenedithiolate exerts pronounced influences on electronic and coordination structure of the metal complexes.  相似文献   
2.
We construct 2-solitary wave solutions with logarithmic distance to the nonlinear Schrödinger equation,
i?tu+Δu+|u|p?1u=0,tR,xRd,
in mass-subcritical cases 1<p<1+4d and mass-supercritical cases 1+4d<p<d+2d?2, i.e. solutions u(t) satisfying
6u(t)?eiγ(t)k=12Q(??xk(t))6H10
and
|x1(t)?x2(t)|2log?t,ast+,
where Q is the ground state. The logarithmic distance is related to strong interactions between solitary waves.In the integrable case (d=1 and p=3), the existence of such solutions is known by inverse scattering (E. Olmedilla, Multiple pole solutions of the nonlinear Schrödinger equation, Physica D 25 (1987) 330–346; T. Zakharov, A.B. Shabat, Exact theory of two-dimensional self-focusing and one-dimensional self-modulation of waves in nonlinear media, Sov. Phys. JETP 34 (1972) 62–69). The mass-critical case p=1+4d exhibits a specific behavior related to blow-up, previously studied in Y. Martel, P. Raphaël (Strongly interacting blow up bubbles for the mass critical NLS, Ann. Sci. Éc. Norm. Supér. 51 (2018) 701–737).  相似文献   
3.
Chen  Ti  Shan  Jinjun  Ramkumar  Ganesh 《Nonlinear dynamics》2018,93(3):1705-1718
Nonlinear Dynamics - This paper presents distributed adaptive tracking control algorithms under fixed or switching communication graph for a team of agents, each of which is a special class of...  相似文献   
4.
5.
A prompt gamma neutron activation analysis borehole logging method for copper, nickel and iron grade estimation is proposed. The performance of the method was simulated by MCNP5 code. Based on the theory of neutron–gamma distribution on the borehole condition, the BGO scintillator and 3He neutron tube are adopted to record gamma ray spectrum and thermal neutron simultaneously, and least square method is used for the characteristic gamma ray counts calculation in the high energy range. The results of detection limit of metal grade in borehole condition indicate that the effectiveness of this logging method.  相似文献   
6.
Hepatitis B core antigen (HBcAg) expressed in Escherichia coli is able to self‐assemble into large and small capsids comprising 240 (triangulation number T = 4) and 180 (triangulation number T = 3) subunits, respectively. Conventionally, sucrose density gradient ultracentrifugation and SEC have been used to separate these capsids. However, good separation of the large and small particles with these methods is never achieved. In the present study, we employed a simple, fast, and cost‐effective method to separate the T = 3 and T = 4 HBcAg capsids by using native agarose gel electrophoresis followed by an electroelution method (NAGE‐EE). This is a direct, fast, and economic method for isolating the large and small HBcAg particles homogenously based on the hydrodynamic radius of the spherical particles. Dynamic light scattering analysis demonstrated that the T = 3 and T = 4 HBcAg capsids prepared using the NAGE‐EE method are monodisperse with polydispersity values of ~15% and ~13%, respectively. ELISA proved that the antigenicity of the capsids was not affected in the purification process. Overall, NAGE‐EE produced T = 3 and T = 4 capsids with a purity above 90%, and the recovery was 34% and 50%, respectively (total recovery of HBcAg is ~84%), and the operation time is 15 and 4 times lesser than that of the sucrose density gradient ultracentrifugation and SEC, respectively.  相似文献   
7.
8.
Several batch experiments were conducted on the anaerobic co-digestion of dairy cow manure (DCM) with three harvest residues (HR) (soybean straw, sunflower stalks, and corn stover). The influence of thermal pretreatment of HR on biogas production was investigated, where the HR were thermally pretreated at two different temperatures: T = 121 °C and T = 175 °C, during t = 30 and t = 90 min, respectively. All anaerobic co-digestion batch experiments were performed simultaneously under thermophilic regime, at T = 55 °C. Biogas and methane yields were significantly improved in experiments performed with corn stover thermally pretreated at 175 °C for 30 min (491.37 cm3/g VS and 306.96 cm3/g VS, respectively), if compared to experiments performed with untreated corn stover. The highest VS and COD removal rates were also observed in the same group of experiments and were 34.5 and 50.1%, respectively. The highest biogas and methane yields with soybean straw (418.93 cm3/g VS and 261.44 cm3/g VS, respectively) were obtained when soybean straw pretreated at 121 °C during 90 min. The highest biogas and methane yields with sunflower stalk (393.28 cm3/g VS and 245.02 cm3/g VS, respectively) were obtained when sunflower stalk was pretreated at 121 °C during 90 min.  相似文献   
9.
Abstract

The experimental evidence concerning the nitration of 1,2,3-benzothiadiazole is conflicting. We have found that 4-nitro- and 7-nitro-1,2,3-benzothiadiazole are the major products, while from 6-chloro-1,2,3-benzothiazole 6-chloro-7-nitro-benzothiadiazole (I) was formed as the only product.  相似文献   
10.
郭提  陈吉祥  李克伦 《催化学报》2012,33(7):1080-1085
在303,514和543K下用0.8%H2O-99.2%H2对Ni2P/SiO2催化剂进行了水蒸气处理,利用N2吸附-脱附、X射线衍射、电感耦合等离子体发射光谱、H2程序升温脱附及原位漫反射红外光谱等技术对水蒸气处理前后Ni2P/SiO2催化剂的结构进行了表征,并在常压固定床反应器上评价了其催化氯苯加氢脱氯活性.结果表明,经水蒸气处理后,Ni2P/SiO2催化剂的物相及元素组成、Ni2P晶粒大小、比表面积及孔结构没有明显改变.与未处理和303K处理的Ni2P/SiO2催化剂不同,513和543K处理的催化剂表面暴露的Ni中心数量减少,表面P–OH基团数量增多.在513K,氯苯空速3.75ml/(g·h)及H2和氯苯的摩尔比为9.0的反应条件下,经不同温度水蒸气处理的Ni2P/SiO2催化剂上氯苯初始转化率高于93.8%,约是未预处理催化剂的17倍.这可能与金属Ni中心和表面P–OH基团的协同作用有关.  相似文献   
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