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In recent years, hydraulic fracturing has emerged as an important technique for the development of unconventional tight gas and oil reservoirs, particularly shale reservoirs. Production from a tight reservoir requires hydraulic creation of a highly fractured network for significantly improving the hydraulic conductivity of the reservoir. Field observations have empirically indicated that fracture complexity tends to be higher in the case of higher rock brittleness which is defined as the combination of the Young's modulus and Poisson's ratio of a rock. The brittleness is considered as one of the most important mechanical rock properties of unconventional tight reservoirs. However, the physical relationship between fracture complexity and the brittleness remains unclear. In this study, a series of hydraulic fracturing simulations were performed using a flow-coupled discrete element method to gain insights into the effect of the brittleness on fracture propagation. The brittleness was adjusted under different combinations of Young's modulus and Poisson's ratio for four rock models. Considering mechanical rock properties and pre-existing fractures, the effective stress in the case of lower brittleness reduced to the tension only around the tip of the hydraulic and pre-existing fractures. On the contrary, the tensile region was more widely distributed along the pre-existing fracture in the case of higher brittleness. The effective tensile stress in a wider region should induce more microcracks, thereby enhancing the possibility of the hydraulic fracture branching off from the pre-existing fracture. These considerations indicate a positive correlation between the brittleness and the complexity of a hydraulically induced fracture system. [ABSTRACT FROM AUTHOR]

A new method of diametrical core deformation analysis (DCDA) is proposed for evaluating the in-situ stress of rocks from an elliptical deformation of boring cores following stress relief. When a piece of rock at depth is cut out to be a core sample by drilling, it becomes free from the in-situ stresses resulting in the expansion of its diameter. Even if the rock is homogeneous and isotropic, the core sample should expand in an asymmetric manner with the relief of anisotropic in-situ stresses. A newly developed apparatus allows us to measure the asymmetric variation of the core diameter. The difference between the maximum and minimum stress components and the stress orientations in a plane perpendicular to the drilled hole can then be estimated from the circumferential variation of the measured core diameters based upon a theoretical relationship between the in-situ stresses and the core diameters, assuming elastic deformation. We carried out laboratory experiments in which core samples were cut out from cubic specimens under uniaxial compression, and we confirmed that the stress magnitude and orientation estimated from the measured core diameters by the proposed DCDA method agreed well with those of the actually applied stress. [ABSTRACT FROM AUTHOR]

Cyclic phosphorus compounds, 6 H-dibenz[ c, e][1,2]oxaphosphorin-6-oxide derivatives, were efficiently synthesized by the Friedel-Crafts reaction of 2-hydroxybiphenyls with phosphorus trichloride in the presence of superacids, especially trifluoromethanesulfonic acid (Tf OH) as a catalyst. Tf OH was investigated for the first time as an effective catalyst for the aromatic phosphination of 2-hydroxybiphenyls. [ABSTRACT FROM AUTHOR]

• We propose a new stress measurement method. • The stress state is recorded by the shape of a core extracted by a novel core drilling approach. • The proposed drilling tool works mechanically without any devices sensitive to high temperature. • Laboratory experiments and numerical simulations support the validity of this concept. We discuss the possibility of recording the state of in-situ stress in the shape of a rock core that is sampled using a modified core drilling method. This concept is based on a phenomenon that a cylindrical rock-core expands radially into a slightly elliptical shape along its transverse cross-section when the rock sample is relieved of its in-situ anisotropic stress by drilling. The magnitudes and orientation of in-situ stresses can, in principle, be estimated from the circumferential variation of core expansion. However, it is not possible to evaluate the expansion from a core collected in a conventional way, with a single drilling bit, since it will be in its expanded state when extracted and lacks information about its required pre-expansion dimensions. To overcome this problem, we propose an innovative way of core drilling referred to as Dual-bit Coring. This approach results in a single core that has two signature transverse cross-sections: the first has an elliptical shape resulting from core expansion and the second records the initial circular shape prior expansion. Then, the amount of expansion can be estimated based on the differences between the shapes of those cross-sections. We propose practical drilling tool for carrying out Dual-bits Coring. The tool works mechanically and does not require any electric devices sensitive to high temperatures so that it is expected to function even in deep and high temperature rocks at geothermal fields, such as those encountered in supercritical geothermal systems. [ABSTRACT FROM AUTHOR]

Using tick-by-tick data for the dollar–yen and euro–dollar exchange rates recorded on the actual transaction platform, a ‘run’—continuous increases or decreases in deal prices for the past several ticks—does have some predictable information on the direction of the next price movement. Deal price movements, that are consistent with order flows, tend to continue a run once it is started. Indeed, conditional probabilities of a run continuing in the same direction after several consecutive observations exceed 0.5. However, quote prices do not show such a run tendency. Hence, a random walk hypothesis is refuted in a simple test of a run using tick-by-tick data. In addition, a longer continuous increase of the price tends to be followed by a larger reversal. The findings suggest that those market participants who have access to real-time, tick-by-tick transaction data may have an advantage in predicting exchange rate movements. The findings reported here also lend support to the momentum trading strategy. [ABSTRACT FROM AUTHOR]

Abstract: There are infinite number of small pores at inside of almost rocks, while the pore’s shape and the interconnectivity among the pores are dependent on the type of rocks. The existence of such pores brings special feature in mechanical behavior of rocks, different to cases of other materials. For the case when the pressure in a drilled borehole is raised by fluid injection into the borehole in hydraulic fracturing carried out for rock stress measurements, the fluid penetrates through the interconnected pores into a rock from the borehole wall, and the fluid penetration develops the change in pore pressure, i.e., fluid pressure in the pore. The developed pore pressure distribution causes a circumferential stress in compression around the borehole, where the mechanics to cause the additional stress is analogous to thermal stress. Furthermore, the pore pressure affects to loose strength in failure following the Terzaghi effective stress law. The point stress criterion can be applied to predict tensile failure of rock occurring in such complicated conditions. Then we should assume that the fracture initiation occurs when the maximum effective stress reaches the tensile strength of a rock at a point that is not on the borehole wall but is inside the rock. This approach allows us to interpret quantitatively strange phenomena associated with fluid permeation such that breakdown pressure, i.e., a critical borehole pressure to cause the tensile failure, increases with the rate of borehole pressurization. [Copyright &y& Elsevier]

Abstract: A novel and efficient synthesis of 3,4,5-triaryltetrahydro-1,4-thiazine derivatives by treatment of β,β′-dichloro sulfides, 2:1 adducts of alkenes and sulfur dichloride, with aromatic amines in the presence of silica gel is described. The silica gel can be easily recovered and reused in up to four consecutive reactions without any significant decrease in product yield. [Copyright &y& Elsevier]

A variety of aromatic aldimines react with nonactivated alkyl iodides in the presence of zinc powder and a catalytic amount of chlorotrimethylsilane (TMSCl) in ethyl acetate–DMI to afford the corresponding α-alkylbenzylamine derivatives in good to excellent yields. [Copyright &y& Elsevier]

— We addressed effects of in situ stress on the formation of flow pathways in fractured rocks in geothermal reservoirs, especially for HDR projects. Here we focused on fractures which are critically-stressed, causing shear slip in a current stress field. The sliding is likely to break sealing in the fractures and, as a result, to increase their permeability. Such a mechanism is possibly significant under high-temperature conditions at geothermal fields because of temperature enhancement on chemical reactions for the sealing. We present a procedure to estimate the orientation of the critically-stressed fractures relative to axes of in situ principal stress with the aid of the Mohr diagram. The procedure allows us to evaluate intuitively how the orientation changes with factors such as magnitude of in situ principal stresses and pore pressure. We applied the procedure to estimate possible orientations of the critically-stressed fractures in major HDR test sites. Results show that overall alignments of microseismicity during hydraulic stimulation are within predicted ranges for possible orientations of the critically-stressed fractures. Furthermore, it was found that if the state of in situ stress is not favorable to cause sliding of natural fractures, it tends to lead a high wellhead pressure at hydraulic stimulation and a high recovery rate at circulation. On the other hand, if the state of in situ stress is favorable for sliding, it tends vice versa to lead a low wellhead pressure at hydraulic stimulation and a low recovery rate at circulation. [ABSTRACT FROM AUTHOR]

[Poly(ethyleneglycol)]-modified hemoglobin vesicles (PEG-HbV), a type of encapsulated hemoglobin, have been developed as artificial oxygen carriers and it is important to evaluate their blood compatibility. We studied the effects of PEG-HbV on human polymorphonuclear neutrophils (PMNs) in vitro, focusing on the functional responses to N-formyl-methionyl-leucyl-phenylalanine (fMLP) as an agonist. The pretreatment of the PMNs with PEG-HbV up to a concentration of 60 mg/dl Hb did not affect the fMLP-triggered chemotactic activity. In parallel to these results, the fMLP-induced upregulation of CD11b(Mac-1) levels on the PEG-HbV-pretreated PMNs was comparable to that of untreated cells. Furthermore, the pretreatment of the PMNs with the PEG-HbV even at 600 mg/dl Hb did not affect the gelatinase B (Matrix methalloproteinase-9 (MMP-9)) release, suggesting that the fMLP-induced release of secondary and tertiary granules was normal. In addition, the fMLP-triggered superoxide production of the PMNs was unchanged by the pretreatment with the PEG-HbV at 600 mg/dl Hb. Thus, these results suggest that PEG-HbV, at the concentrations studied, have no aberrant effects on the fMLP-triggered functions of human PMNs. [ABSTRACT FROM AUTHOR]

• We propose a method to evaluate flow pathways in geothermal reservoirs. • Our method utilizes microseismic and in-situ stress information. • The flow pathway model is optimized to fit the inferred pore pressure distribution. • Our method could discover fluid flow features in the Basel EGS field. Evaluation of fluid flow behavior is important for understanding various phenomena in a geothermal reservoir. Microseismic monitoring and location can be used to track pore pressure migration to some extent; however, microseismic information cannot directly provide the detail of flow behavior, such as how fluid flow occurs in the reservoir. In this study, we propose a new method to evaluate the entire flow-path system in a fractured reservoir. We first estimate the pore-pressure increase for each microseismic event based on microseismic and in-situ stress information. We extend the discrete pore pressure data to a continuous distribution based on the idea of a main flow pathway and sub flow pathways. We also introduce a honeycomb-shaped flow pathway model, which consists of flow pathways and nodes. Hydraulic parameters are different between different flow pathways. To match observed pore pressures at the nodes, an optimization process is used to adjust the hydraulic parameters for each flow pathway. We get a proxy of the hydraulic conductivity distribution based on the flow pathway model, that can evaluate flow pathways and flow behavior. We apply this method to hydraulic stimulation and microseismic data from the Basel enhanced geothermal system (EGS) project. Our method successfully delineated the main permeable zone and caught the tendency of fluid flow behavior that is also indicated by other microseismic analysis. Our method can catch the qualitative behavior of fluid flow in the geothermal reservoir and can contribute to designing geothermal energy extraction systems and forecasting. [ABSTRACT FROM AUTHOR]

The shale rock, with relatively low permeability and porosity, is usually challenging to be developed economically. Hydraulic fracturing is widely used as a stimulation technique for shale gas exploitation. Unlike tight gas reservoirs, shale gas reservoirs appear to show different characteristics under hydraulic fracturing, with a low flow-back rate leading to high productivity. This might be linked to micro-cracks generated by the clay swelling when fluid penetrates the rock, as shown in previous fracturing experiments. However, detailed failure patterns and associated permeability changes under different conditions (e.g., in-situ stress, pore pressure, and clay content) remain ambiguous. In this study, numerical simulations were adopted to address these issues. A solid model with cohesive elements based on the Finite element method was used to predict the generation of micro-cracks. Further, a permeability evaluation model considering the micro-cracks was applied to estimate the permeability changes. Our simulation results indicate that clay swelling can produce shear cracks. The number of shear cracks is substantially influenced by the swelling stress and clay contents. Tensile cracks, together with a complex fracture network, can be observed when the pore pressure or stress difference increases. The permeability increases significantly when a complex fracture network is formed. This study reveals that micro-cracks can be induced by the interaction between fracturing fluid and shale rock, which may help explain how low flow-back rate results in high productivity in shale gas reservoirs. • A numerical model including a solid model and permeability evaluation model has been developed. • Influences of different conditions on micro-cracks and permeability changes have been investigated. • A complex fracture network can be formed by fracturing, resulting in a significant increase in permeability. [ABSTRACT FROM AUTHOR]

In December 2007, an Mw2.2 earthquake occurred in a gabbroic dike at 3.3 km depth in a deep gold mine in South Africa. The fore- and aftershock activity was analyzed in an effort to understand the preparation and generation processes of earthquakes; these findings have already been published. The present paper focuses on the stress state in the source region of the mainshock. A 90-m-long borehole across the mainshock fault was drilled ~ 1.5 years after the mainshock and logged by an optical televiewer. The fault can be identified by severe damage to the borehole wall at the point where the borehole intersected the aftershock cluster. Except for a 10-m section in the hanging wall of the fault, borehole cores were fully recovered. Borehole breakout (BO) and core disking (CD) were found to occur. Two stress measurement techniques [Deformation Rate Analysis (DRA) and Diametrical Core Deformation Analysis (DCDA)] were applied to the borehole cores. By combining their results with occurrence criteria for BO and CD, the principal stress state in the source region of the mainshock was determined. The principal directions in the hanging wall of the fault were nearly identical to the virgin stress state, while it was significantly disturbed in the footwall. The vertical stresses were 106 MPa and 40 MPa in the hanging wall and footwall, respectively. The significant difference in the vertical stress between the two sides of the fault can be explained by the stress redistribution associated with a nonuniform slip on a nonplanar fault. [ABSTRACT FROM AUTHOR]

Fracture patterns induced by supercritical-water fracturing show complex fracture networks with branched and isolated fractures. Such fracture patterns are expected to effectively increase permeability and significantly improve the heat exchange surface area. We clarify the mechanism of complex fracture induced by supercritical water using a coupled model and discuss the performance of the supercritical-water fracturing under geothermal environments. The numerical approaches to the coupled model are the pore-scale network method and finite element method with cohesive elements. Supercritical-water fracturing in granite at the laboratory scale was simulated and compared with the experimental results. The simulation results of fracture patterns are in good agreement with the experimental results. The results suggest that low viscosity of supercritical water leads to a strong seepage effect in granite, which reduces the effective stress over a wide area and makes it easier for shear failures to occur. We also found that differential stress and large confining stress induce more complex cloud-fracture networks. Our results clearly show that fracturing with supercritical water is effective not only for the geothermal resources that are considered so far but also for the development of the area at even deeper depths, which can contribute a leap forward in geothermal development. • A coupled flow-solid model was developed to simulate supercritical water fracturing. • Mechanism of forming cloud–fracture networks induced by supercritical water fracturing was revealed. • The low viscosity of supercritical water was recognized as the main cause of cloud–fracture networks. • Large differential stress and large confining stress conditions induce more complex cloud-fracture networks. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the early quality of life outcomes in prostate cancer patients managed by high-dose-rate brachytherapy as monotherapy. Methods: A total of 51 patients with cT1c-T3aN0M0 prostate cancer treated between July 2007 and January 2010 were included in this study. The average age was 69 years, and the average initial serum prostate-specific antigen was 10.98 ng/mL. A total of 25, 18 and eight patients were considered to be low, intermediate and high risk, respectively. All patients received one implant of Ir-192 and seven fractions of 6.5 Gy within 3.5 days for a total prescribed dose of 45.5 Gy. For high-risk prostate cancer, neoadjuvant androgen deprivation therapy was carried out for at least 6 months, and continued after high-dose-rate brachytherapy. Quality of life outcomes were measured by using the International Prostate Symptom Score, the Functional Assessment of Cancer Therapy-Prostate and the International Index of Erectile Function Questionnaire. The oncological outcome was assessed by serum prostate-specific antigen and diagnostic imaging. Adverse events were also recorded. Results: The Functional Assessment of Cancer Therapy-Prostate scores decreased for a few months after high-dose-rate brachytherapy, and recovered to pretreatment condition thereafter. The International Prostate Symptom Score significantly increased 2 weeks after treatment for each of its items and their sum, and it returned to baseline after 12 weeks. Sexual function decreased at 2 and 4 weeks, and recovered after 12 weeks. Severe complications were rare. Within a median follow up of 17.2 months, two patients showed a prostate-specific antigen recurrence. Conclusions: High-dose-rate brachytherapy for prostate cancer is a feasible treatment modality with acceptable toxicity and only a limited impact on the quality of life. [ABSTRACT FROM AUTHOR]

Introduction: A retroperitoneoscopic nephrectomy (RN) for symptomatic hydronephrosis (SH) is a challenging procedure because of the limited working space. This report describes a specific technical modification for efficient and successful RN for SH by using the SAND balloon catheter. Patient and Methods: A 38-year-old woman underwent RN for SH caused by extrinsic compression of the ureter by a pelvic endometriosis. The SAND balloon catheter was directly inserted into the expanded hydronephrotic sac, and the liquid was extracted, appropriately. Urine leakage from the hydronephrotic sac could be avoided because the puncture site was sealed firmly between the two adjacent balloons at the tip of the catheter. Disposal counter traction using the catheter facilitated the mobilization of the hydronephrotic sac. Results: The patient was discharged 3 days after undergoing this procedure. Conclusions: This method improves the surgeon's vision and facilitates resection without causing any injury to the hydronephrotic sac wall during RN. [ABSTRACT FROM AUTHOR]

Background: Recent reports on laparoscopic surgery for urachal anomalies have not described any techniques to restore the natural appearance of the umbilicus. In this report, we present a simple technique that enables complete resection of urachal anomalies while preserving the natural appearance of the umbilicus. Materials and Methods: Laparoscopic excision of symptomatic urachal anomalies was performed for 4 men and 2 women. After dissecting the urachal lesion along the preperitoneal plane toward the umbilicus, the cephalic side of the lesion was ligated and the skin at the base of the umbilicus was divided while compressing the anterior abdominal wall to ensure complete removal of the lesion. Results: The laparoscopic procedure was successfully completed with minimal blood loss, and the umbilicus could be restored to its natural appearance in all the cases. Conclusions: This is the first report to describe a procedure for restoring the natural appearance of the umbilicus. This simple, alternative approach yields better cosmetic results and, therefore, will be useful, especially in younger patients. [ABSTRACT FROM AUTHOR]

An industrial and economic carbonylation of amines with carbon monoxide and sulfur has been developed for the synthesis of S-alkyl thiocarbamate herbicides. In the presence of potassium carbonate and solvent DMSO, S-alkyl thiocarbamates, such as thiobencarb and orbencarb (herbicides) are synthesized in excellent yields from amines, carbon monoxide, sulfur, and alkyl halides under mild conditions (1 atm, 20 °C). [Copyright &y& Elsevier]

Topological data analysis is an emerging concept of data analysis for characterizing shapes. A state-of-the-art tool in topological data analysis is persistent homology, which is expected to summarize quantified topological and geometric features. Although persistent homology is useful for revealing the topological and geometric information, it is difficult to interpret the parameters of persistent homology themselves and difficult to directly relate the parameters to physical properties. In this study, we focus on connectivity and apertures of flow channels detected from persistent homology analysis. We propose a method to estimate permeability in fracture networks from parameters of persistent homology. Synthetic 3D fracture network patterns and their direct flow simulations are used for the validation. The results suggest that the persistent homology can estimate fluid flow in fracture network based on the image data. This method can easily derive the flow phenomena based on the information of the structure. [ABSTRACT FROM AUTHOR]

Nano- and microparticles are expected to have several functionalities, and the ability to control size and shape is an advantage of using nano-/microparticles. This study investigated a possibility that the sizes of nano-/microparticle can be used to extract new information on structures in a fractured medium. Flow experiments were conducted to observe the particle transport in a micromodel on which a single fracture and rock matrix (grain and pore space) was fabricated on a silicon wafer. Water and nano-/microparticles were injected into the micromodel, and the droplets were collected at the outlet. Tunable Resistive Pulse Sensing (TRPS) was used to measure the frequency distributions of particle diameters from each droplet at each time. The result shows that the larger particles were observed only at early time, while the smaller particles were detected at early time and also at late time. This indicates that the larger particles flow in a fracture quickly, while smaller particles migrate through both fracture and matrix over a wider range of time. Particles with different sizes transport through fractured media differently depending on the fracture structures. The tracer response of nano- and microparticles may be useful to evaluate the fracture structures and the flow properties for different flow pathways. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing using water-based fluid consumes a large amount of freshwater resources and pollutes a reservoir by substantially decreasing its matrix permeability. To address the problems caused by water-based fracturing fluids, the possibility of using SC-CO 2 as a fracturing fluid was studied for its special properties (such as low viscosity, high density, and miscibility with hydrocarbons). Previous experimental studies have indicated that SC-CO 2 is superior to water-based fracturing fluid in inducing complex fractures at the laboratory scale, while the mechanism of complex fractures induced by SC-CO 2 remains unclear. This study develops a new numerical model to simulate the different performances of SC-CO 2 fracturing and water-based fluid fracturing to determine the mechanisms of complex fractures. The numerical model couples an unsteady flow model based on the pore-scale network method and a solid model using the finite element method with cohesive zone elements. The unsteady flow model reproduces a two-phase flow considering viscous and capillary forces at the pore scale. Our simulation results show that both viscous and capillary forces contribute to the different fracturing performances between SC-CO 2 and water-based fluid. The capillary force should be considered in the flow model when simulating fracturing in low matrix permeability rock. [ABSTRACT FROM AUTHOR]

Supercritical carbon dioxide (SC-CO 2) fracturing is a promising technology for unconventional energy development and carbon capture and storage. Experimental studies have shown that SC-CO 2 fracturing can form complex fracture networks and reduce crack initiation pressure, which are different results from those when fracturing with aqueous fluids. The complex fracture networks that form from SC-CO 2 fracturing may be the result of strong seepage effects (i.e., low capillary and viscous forces). To understand the different injection behaviors induced by SC-CO 2 and aqueous fluids in low-permeability rocks, this study develops a new two-phase steady-state model based on the pore-scale network method. Although other models consider the viscous force, our model implements the capillary and viscous forces to reproduce the seepage effect. Because of the capillary force, the flow model is nonlinear and solved by iteratively solving matrix equations until a conservation of volumetric flux is satisfied. Simulation results show that the capillary force in a two-phase flow system in small pore spaces has consequential effects on its pressure distribution. Such factors lead to discontinuous pressure drops. This study shows that the seepage effect of SC-CO 2 is stronger than that of aqueous fluids and can largely avoid the capillary blockage that arises in oil-water systems. • The seepage effect estimation model for supercritical CO 2 and water fracturing in unconventional gas reservoir is proposed. • The simulation results show that capillary force has strong effect on seepage effect. • The strong seepage effect of SC-CO2 is a key factor to form complex fractures. [ABSTRACT FROM AUTHOR]

As a part of ICDP-DSeis project, we determined in-situ stress states around the source faults of three earthquakes: a Mw2.2 earthquake at ~3.3 km depth in Mponeng mine, a M3.5 earthquake at ~3.5 km depth in Savuka mine, and the Orkney earthquake (Mw5.5), with its hypocenter ~5 km beneath Moab Khotsong mine. Criteria of core disking and borehole breakout were evaluated to constrain stresses in Mponeng mine. The Diametrical Core Deformation (DCDA) and the Deformation Rate Analysis (DRA) were applied to determine the differential and the normal stresses, respectively, from core samples recovered at Mponeng and Moab Khotsong mines. The Compact Conical-ended Borehole Overcoring (CCBO) was carried out in Savuka mine. By integrating these data, we extracted characteristics of the stress state in the earthquake source region. [ABSTRACT FROM AUTHOR]

Chloroboron(III) hexabromosubnaphthalocyanine was prepared by cyclotrimerization of 6,7-dibromo-2,3-naphthalenedicarbonitrile in the presence of BCl 3 under high dilution conditions, that is 7.4 mM of dicarbonitrile in o -dichlorobenzene-xylene (1:1). It was converted to fluoroboron(III) hexabromosubnaphthalocyanine by the reaction with AgBF 4 . Fluorescence quantum yields of chloroboron(III) hexafluoro-, hexachloro-, hexabromo-, and hexaiodosubnaphthalocyanine were 0.22, 0.20, 0.11, 0.05, respectively, indicating that heavy atom effects of Br and I effectively deactivated the singlet excited states. Thermal decomposition temperature (5% weight loss in the TG curve) of fluoroboron(III) hexabromosubnaphthalocyanine was the highest (359 °C) and that of chloroboron(III) hexafluorosubnaphthalocyanine was the lowest (221 °C) among hexahalosubnaphthalocyanines. The hexabromosubnaphthalocyanine served as a substrate of Sonogashira coupling, and proved to be a useful intermediate for further functionalization of subnaphthalocyanines. [ABSTRACT FROM AUTHOR]

To better understand the distribution of three dimensional stress states in the Nankai subduction zone, southwest Japan, we review various stress-related investigations carried out in the first and second stage expeditions of the Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) by the Integrated Ocean Drilling Program (IODP) and compile the stress data. Overall, the maximum principal stress σ 1 in the shallower levels (<~1 km) is vertical from near the center of forearc basin to near the trench and; the maximum horizontal stress S Hmax (interpreted to be the intermediate principal stress σ 2 ) is generally parallel to the plate convergence vector. The exception to this generalization occurs along the shelf edge of the Nankai margin where S Hmax is along strike rather than parallel to the plate convergence vector. Reorientation of the principal stresses at deeper levels (e.g., >~ 1 km below seafloor or in underlying accretionary prism) with σ 1 becoming horizontal is also suggested at all deeper drilling sites. We also make a comparison of the stress state in the hanging wall of the frontal plate-interface between Site C0006 in the Nankai and Site C0019 in the Japan Trench subduction zone drilled after the 2011 Mw 9.0 Tohoku-Oki earthquake. In the Japan Trench, a comparison between stress state before and after the 2011 mega-earthquake shows that the stress changed from compression before the earthquake to extension after the earthquake. As a result of the comparison between the Nankai Trough and Japan Trench, a similar current stress state with trench parallel extension was recognized at both C0006 and C0019 sites. Hypothetically, this may indicate that in Nankai Trough it is still in an early stage of the interseismic cycle of a great earthquake which occurs on the décollement and propagates to the toe (around site C0006). [ABSTRACT FROM AUTHOR]

Chloroboron(III) hexachloro- and hexaiodosubnaphthalocyanines were prepared, and their solubility, electronic absorption spectroscopy, fluorescence emission spectroscopy and HOMO/LUMO energy levels were evaluated. These subnaphthalocyanines showed lower HOMO/LUMO energies than the parent subnaphthalocyanine by 0.13–0.39 eV. The optical band gap decreased in the order: hexafluoro->hexachloro->unsubstituted>hexaiodo-subnaphthalocyanine. Fluorescence quantum yield of hexaiodosubnaphthalocyanine was 0.05, significantly lower than those of the parent, hexafluoro- and hexachloro-subnaphthalocyanines whose quantum yields ranged from 0.2 to 0.22, indicating that the heavy atom effects of iodine work effectively. [ABSTRACT FROM AUTHOR]

Methanofullerenes bearing both an ethyleneoxy side chain, −(CH 2 CH 2 O) n -, n = 1 or 2, and a 5-ethyl-2-thienyl group were prepared. These methanofullerenes were much more polar than PCBM and C 60 , and solubility in chlorobenzene (23–24 g/L) was comparable to that of PCBM. Planar heterojunction photovoltaic cells employing the methanofullerenes as an electron acceptor and copper phthalocyanine (CuPc) as an electron donor were fabricated. The short-circuit current density of the photovoltaic cell (4.61–4.66 mA/cm 2 ) was larger than that of the photovoltaic cell prepared from the standard fullerene acceptor, PCBM, (4.08 mA/cm 2 ), and consequently the power conversion efficiency was improved. Comparisons of contact angles of water and hexadecane on fullerene films indicated that the fullerenes with an ethyleneoxy side chain formed more stable interface with CuPc than PCBM. These results suggest that side chain engineering aiming at stable p - n interface is an attractive strategy for designing efficient organic photovoltaic cells. [ABSTRACT FROM AUTHOR]

A new method for the hydrolysis of diazonium salts, without the formation of tar, was developed. A two-phase system consisting of cyclopentyl methyl ether (CPME) and water is very effective for the hydrolysis of diazonium salts. Using this solvent system, the diazonium salt prepared from 3-(4-nitrophenoxy)aniline gave 3-(4-nitrophenoxy)phenol in high yield (96%) within 20 min. The synthesized phenol is an industrially important raw material in polymer syntheses. Furthermore, the use of the present two-phase system of CPME and water successfully brought about the efficient conversions of several m-substituted anilines into the corresponding m-substituted phenols. This is the first example of hydrolysis of diazonium salts using the two-phase system (CPME and water). [ABSTRACT FROM AUTHOR]

Methanofullerenes, such as [6,6]-phenyl-C61-butyric acid methyl ester {[6,6]PC61BM (1a)}, were synthesized in good yields from the corresponding tosylhydrazones in an aqueous two-phase (o-dichlorobenzene-H2O) system under photoirradiation conditions. This simple and convenient procedure was adopted for the synthesis of thienyl analogues of PC61BM and its C70 analogue, PC71BM. [ABSTRACT FROM AUTHOR]

A catalyst based on iron and elemental sulfur has been shown to efficiently promote a redox-neutral reaction between 2-nitrophenols and 2,6-disubstituted p-cresols, allowing for the preparation of 2-arylbenzoxazoles in good yields. This synthetic methodology also affords high atom economy without the use of any external oxidizing and/or reducing reagents. This is the first redox-condensation reaction of 2-nitrophenols with 2,6-disubstituted p-cresols. [ABSTRACT FROM AUTHOR]

A series of arylated dihydrofullerene derivatives were synthesized to elucidate the effective design of fullerene derivatives for enhancing the performance of organic photovoltaics. The LUMO energy of the fullerenes was estimated by the first reduction potential and theoretical calculations. The results showed that the methoxy groups substituted at spatial proximity to the fullerene core offered significant stabilization of the LUMO level. The stabilizing effect of the directly arylated fullerenes is more significant than that of conventional methanofullerenes. The theoretical investigation was performed with regard to the electronic interaction between the methoxy and fullerene moieties. [ABSTRACT FROM AUTHOR]

Background: Laparoscopic surgery has not yet met with widespread acceptance due to its degree of technical difficulty. The laparoscopic radical nephrectomy procedure was improved with the aid of an abdominal wall sealing device, a wound retractor, and a surgical glove. Methods: A 5 cm skin incision was made at the beginning of the operation. The Alexis wound retractor S was set up through this small incision. The wrist portion of the surgical glove (size 8-0) was then used to cover the outer ring of the wound retractor to maintain pneumoperitoneum. The surgeon can use most of the usual surgical instruments through the wound retractor during the laparoscopic surgery. Results: These procedures were successfully conducted in all cases without open conversion, and no postoperative complications were observed. Conclusions: Glove-assisted laparoscopic surgery can be used to perform advanced laparoscopic procedures. This new technique made laparoscopic abdominal surgery easier and safer for beginners in laparoscopic surgery and skilled surgeons in open surgery. [ABSTRACT FROM AUTHOR]

The efficient cross-coupling reaction to afford ketones from pyridine carboxylic acid chlorides and alkylzinc reagents in the presence of Pd(phen)Cl2 is reported. In the case of chloronico�tinoyl chlorides, none of Negishi cross-coupling products of 2-chloroazine moiety was formed. The catalyst loading could be reduced up to 0.01 mol%. [ABSTRACT FROM AUTHOR]

Abstract: Carbon dioxide (CO2) is considered to be one of the greenhouse gases that may contribute most to global warming on the earth. Disposal of CO2 from stationary sources into subsurface structures has been suggested as a possible means for reducing CO2 emissions into the atmosphere. However, much remains to be done in the issues regarding the safety and reliability of CO2 geological sequestration. In this study, we have developed a simulation code by using the mathematical model of two phase flow in porous media to analyze the flow dynamics in the subsurface. The equation of state for CO2 covering the fluid region from the triple point to the supercritical region is employed to model the states of CO2 gas, liquid and supercritical state. The correct understanding of the CO2 state under the geological formation condition is an important factor to predict the injection pressure and CO2 fluid permeation because the fluid density has a great effect on the injection behavior. The numerical simulation was implemented under several geological conditions including gas, liquid and supercritical states to examine the optimal injection condition. Comparing the numerical results obtained using the equation of state for CO2 with those obtained using the ideal gas equation, it has been shown that the difference in the injection pressure appears to be significant near the condition of the critical point of CO2 and the phase equilibrium curves between the gas and liquid states. The numerical simulation has been implemented to examine the effect of the reservoir condition on the injection behavior. The injection pressure is decreased at the lower reservoir temperature and higher hydrostatic pressure condition. The CO2 permeation is also strongly affected by the reservoir condition, and the spatial CO2 saturation becomes higher with increasing reservoir temperature. It has been demonstrated that the simulation code developed in this study may be useful to provide knowledge required to select the reservoir condition for CO2 geological sequestration. [Copyright &y& Elsevier]

Abstract: Efficient oxidation system using reusable vanadyl(IV) sulfate catalyst was established. Toluenes were easily oxidized under molecular oxygen (0.1MPa) at 100°C catalyzed by vanadyl(IV) sulfate to afford the corresponding benzoic acids in excellent yields. The recovered catalyst could be reused without loss of activity. [Copyright &y& Elsevier]

An efficient, eco-friendly, and mild method for the acylation of various nucleophiles with acid anhydrides using iron(III) chloride is described. The addition of only 0.1-2 mol% of iron chloride catalyzed the acylation under solvent-free conditions at room temperature to give the acylated products in good yields. [ABSTRACT FROM AUTHOR]

A reduction of organic solvents in the organic chemical industry is of serious importance for sustainable chemistry. With this viewpoint, we successfully established the useful dehydrogenation of hydrazo compounds using basic alumina or KF/alumina �under solvent-free conditions to afford azo compounds in good to excellent yields. [ABSTRACT FROM AUTHOR]

En-echelon veins are a set of tensile fractures that develop during the initiation of shear zones under certain conditions, but factors that control fracture patterns remain unclear. In this study, we performed numerical simulations using the two-dimensional distinct element method to understand the influence of effective normal stress on the development of fractures during shear deformation. At low effective normal stress (10 MPa), dilation takes place at an angle of ≈40°–45° to the shear boundary, and en-echelon arrays of tensile fractures develop. In contrast, at high effective normal stress (150 MPa), en-echelon veins are not developed, but a distinct shear plane forms. A transient behavior characterizes intermediate effective normal stress (≈50 MPa): early tensile cracks are generated and then propagate to form larger brittle faults. In this case, the larger strain energy released in the later stage is due to the greater shear strength. Under crustal conditions, effective normal stress varies, due to the change in fluid pressure. Our results suggest that en-echelon veins are indicators of high fluid pressure, close to lithostatic conditions, i.e. effective normal stress close to zero, and that a transition of the failure mode from tensile to shear could occur in response to a dynamic change of fluid pressure during fracturing. • The formation of en-echelon veins is investigated using the distinct element method. • Fracture patterns in shear zones vary with effective normal stress. • En-echelon veins form preferentially at near-lithostatic fluid pressures. • Changes in fluid pressure induce transitions in fracture patterns. [ABSTRACT FROM AUTHOR]

Substitution of 2,6-di-tert-butyl-p-cresol (II) by 2-tert-butyl-p-cresol, 2,6-dimethoxy-p-cresol or 1-tert-butyl-toluene results in the isolation of the corresponding products in small or trace amounts only. [ABSTRACT FROM AUTHOR]