Optical, cathodoluminescence and transmission electron microscope (TEM)analyses were conducted on four groups of calcite fault rocks, a cataclastic limestone, cataclasticcoarse-grained marbles from two fault zones, an...Optical, cathodoluminescence and transmission electron microscope (TEM)analyses were conducted on four groups of calcite fault rocks, a cataclastic limestone, cataclasticcoarse-grained marbles from two fault zones, and a fractured mylonite. These fault rocks showsimilar microstructural characteristics and give clues to similar processes of rock deformation.They are characterized by the structural contrast between macroscopic cataclastic (brittle) andmicroscopic mylonitic (ductile) microstructures. Intragranular deformation microstructures (i.e.deformation twins, kink bands and microfractures) are well preserved in the deformed grains inclasts or in primary rocks. The matrix materials are of extremely fine grains with diffusivefeatures. Dislocation microstructures for co-existing brittle deformation and crystalline plasticitywere revealed using TEM. Tangled dislocations are often preserved at the cores of highly deformedclasts, while dislocation walls form in the transitions to the fine-grained matrix materials andfree dislocations, dislocation loops and dislocation dipoles are observed both in the deformedclasts and in the fine-grained matrix materials. Dynamic recrystallization grains from subgrainrotation recrystallization and subsequent grain boundary migration constitute the major parts of thematrix materials. Statistical measurements of densities of free dislocations, grain sizes ofsubgrains and dynamically recrystallized grains suggest an unsteady state of the rock deformation.Microstructural and cathodoluminescence analyses prove that fluid activity is one of the major partsof faulting processes. Low-temperature plasticity, and thereby induced co-existence of macroscopicbrittle and microscopic ductile microstructures are attributed to hydrolytic weakening due to theinvolvement of fluid phases in deformation and subsequent variation of rock rheology. Duringhydrolytic weakening, fluid phases, e.g. water, enhance the rate of dislocation slip and climb, andincrease the rate of recovery of strain-hardened rocks, which accommodates fracturing.展开更多
In this study,a new linear friction welding(LFW)process,embedded LFW process,was put forward,which was mainly applied to combination manufacturing of long or overlong loadcarrying titanium alloy structural components ...In this study,a new linear friction welding(LFW)process,embedded LFW process,was put forward,which was mainly applied to combination manufacturing of long or overlong loadcarrying titanium alloy structural components in aircraft.The interfacial plastic flow behavior and bonding mechanism of this process were investigated by a developed coupling EulerianLagrangian numerical model using software ABAQUS and a novel thermo-physical simulation method with designed embedded hot compression specimen.In addition,the formation mechanism and control method of welding defects caused by uneven plastic flow were discussed.The results reveal that the plastic flow along oscillating direction of this process is even and sufficient.In the direction perpendicular to oscillation,thermo-plastic metals mainly flow downward along welding interface under coupling of shear stress and interfacial pressure,resulting in the interfacial plastic zone shown as an inverted“V”shape.The upward plastic flow in this direction is relatively weak,and only a small amount of flash is extruded from top of joint.Moreover,the wedge block and welding components at top of joint are always in un-steady friction stage,leading to nonuniform temperature field distribution and un-welded defects.According to the results of numerical simulation,high oscillating frequency combined with low pressure and small amplitude is considered as appropriate parameter selection scheme to improve the upward interfacial plastic flow at top of joint and suppress the un-welded defects.The results of thermo-physical simulation illustrate that continuous dynamic recrystallization(CDRX)induces the bonding of interface,accompanying by intense dislocation movement and creation of many low-angle grain boundaries.In the interfacial bonding area,grain orientation is random with relatively low texture density(5.0 mud)owing to CDRX.展开更多
Objective: to analyze the clinical effect of small incision liposuction and continuous catgut embedding double eyelid plasty for asymmetric double eyelid. Methods: 96 patients with asymmetric double eyelid blepharopla...Objective: to analyze the clinical effect of small incision liposuction and continuous catgut embedding double eyelid plasty for asymmetric double eyelid. Methods: 96 patients with asymmetric double eyelid blepharoplasty in our hospital were selected and randomly divided into two groups with 48 cases in each group. The traditional operation was used in the traditional group, while the operation in the cosmetic repair group was combined application of small incision liposuction and continuous catgut embedding double eyelid plasty. The results and effects of cosmetic repair were observed in both groups. Results: compared with the traditional group, the bleeding, healing and operation time of the cosmetic repair group were significantly improved. After treatment, the double eyelid symmetry score was significantly improved, and the satisfaction to the cosmetic effect was significantly improved (P<0.05). Conclusion: the application of small incision liposuction combined with continuous catgut embedding double eyelid plasty can achieve good effect of double eyelid plasty with good aesthetic appearance and shortened course of treatment.展开更多
An immunohistochemical study of T lymphocyte subsets on frozen substituted plastic embedding bone marrow sections obtained from 10 patients with myelodysplastic syndrome (MDS) was presented. The results of qualitative...An immunohistochemical study of T lymphocyte subsets on frozen substituted plastic embedding bone marrow sections obtained from 10 patients with myelodysplastic syndrome (MDS) was presented. The results of qualitative and quantitative immunohistochemical analysis are as follows: (1) Labile antigens of T lymphocytes were well preserved, thus allowing analysis of distribution of T lymphocyte subsets in situ ; (2) the average number of T 3, T 4 and T 8 lymphocyte of the diffuse infiltrate was about 2 %, 0.4 %, 0.5 %, respectively, of all nucleated cells in bone marrow, and T 4/T 8 of T cells were below 1.0 in patients with MDS; (3) there were cases of RAS showing T lymphocyte aggregation in bone marrow, but no patient exhibited progressive refractory anemia with excess of blasts(RAEB) and RAEB in transformation (RAEBT). These findings indicated that the immunological abnormalities are of importance in the evaluation of pathogenesis and prognosis of MDS.展开更多
For the issue of proppant embedment in hydraulic fracturing,a new calculation method of embedment depth considering elastic-plastic deformation was proposed based on the mechanism of proppant embedment into rocks by c...For the issue of proppant embedment in hydraulic fracturing,a new calculation method of embedment depth considering elastic-plastic deformation was proposed based on the mechanism of proppant embedment into rocks by combining proppant embedment constitutive equations and contact stresses on the rock-proppant system.And factors affecting embedment depth of proppant were analyzed using the new method.Compared with the elastic embedment model,the results calculated by the new method match well with the experimental data,proving the new method is more reliable and more convenient to make theoretical calculation and analysis.The simulation results show the process of proppant embedment into rocks is mainly elastic-plastic.The embedment depth of monolayer proppants decreases with higher proppant concentration.Under multi-layer distribution conditions,increasing the proppant concentration will not change its embedment depth.The larger the proppant embedment ratio,the more the stress-bearing proppants,and the smaller the embedment depth will be.The embedment depth under higher closure stress is more remarkable.The embedment depth increased with the drawdown of fluid pressure in the fracture.Increasing proppant radius or the ratio of proppant Young’s modulus to rock Young’s modulus can reduce the proppant embedment depth.展开更多
基金partly financially supported by the State Education Commission and the NNSF(No.49872071).
文摘Optical, cathodoluminescence and transmission electron microscope (TEM)analyses were conducted on four groups of calcite fault rocks, a cataclastic limestone, cataclasticcoarse-grained marbles from two fault zones, and a fractured mylonite. These fault rocks showsimilar microstructural characteristics and give clues to similar processes of rock deformation.They are characterized by the structural contrast between macroscopic cataclastic (brittle) andmicroscopic mylonitic (ductile) microstructures. Intragranular deformation microstructures (i.e.deformation twins, kink bands and microfractures) are well preserved in the deformed grains inclasts or in primary rocks. The matrix materials are of extremely fine grains with diffusivefeatures. Dislocation microstructures for co-existing brittle deformation and crystalline plasticitywere revealed using TEM. Tangled dislocations are often preserved at the cores of highly deformedclasts, while dislocation walls form in the transitions to the fine-grained matrix materials andfree dislocations, dislocation loops and dislocation dipoles are observed both in the deformedclasts and in the fine-grained matrix materials. Dynamic recrystallization grains from subgrainrotation recrystallization and subsequent grain boundary migration constitute the major parts of thematrix materials. Statistical measurements of densities of free dislocations, grain sizes ofsubgrains and dynamically recrystallized grains suggest an unsteady state of the rock deformation.Microstructural and cathodoluminescence analyses prove that fluid activity is one of the major partsof faulting processes. Low-temperature plasticity, and thereby induced co-existence of macroscopicbrittle and microscopic ductile microstructures are attributed to hydrolytic weakening due to theinvolvement of fluid phases in deformation and subsequent variation of rock rheology. Duringhydrolytic weakening, fluid phases, e.g. water, enhance the rate of dislocation slip and climb, andincrease the rate of recovery of strain-hardened rocks, which accommodates fracturing.
基金co-supported by the National Natural Science Foundation of China(Nos.52105411,52105400and 52305420)the China Postdoctoral Science Foundation(No.2023M742830)Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(No.CX2023008).
文摘In this study,a new linear friction welding(LFW)process,embedded LFW process,was put forward,which was mainly applied to combination manufacturing of long or overlong loadcarrying titanium alloy structural components in aircraft.The interfacial plastic flow behavior and bonding mechanism of this process were investigated by a developed coupling EulerianLagrangian numerical model using software ABAQUS and a novel thermo-physical simulation method with designed embedded hot compression specimen.In addition,the formation mechanism and control method of welding defects caused by uneven plastic flow were discussed.The results reveal that the plastic flow along oscillating direction of this process is even and sufficient.In the direction perpendicular to oscillation,thermo-plastic metals mainly flow downward along welding interface under coupling of shear stress and interfacial pressure,resulting in the interfacial plastic zone shown as an inverted“V”shape.The upward plastic flow in this direction is relatively weak,and only a small amount of flash is extruded from top of joint.Moreover,the wedge block and welding components at top of joint are always in un-steady friction stage,leading to nonuniform temperature field distribution and un-welded defects.According to the results of numerical simulation,high oscillating frequency combined with low pressure and small amplitude is considered as appropriate parameter selection scheme to improve the upward interfacial plastic flow at top of joint and suppress the un-welded defects.The results of thermo-physical simulation illustrate that continuous dynamic recrystallization(CDRX)induces the bonding of interface,accompanying by intense dislocation movement and creation of many low-angle grain boundaries.In the interfacial bonding area,grain orientation is random with relatively low texture density(5.0 mud)owing to CDRX.
文摘Objective: to analyze the clinical effect of small incision liposuction and continuous catgut embedding double eyelid plasty for asymmetric double eyelid. Methods: 96 patients with asymmetric double eyelid blepharoplasty in our hospital were selected and randomly divided into two groups with 48 cases in each group. The traditional operation was used in the traditional group, while the operation in the cosmetic repair group was combined application of small incision liposuction and continuous catgut embedding double eyelid plasty. The results and effects of cosmetic repair were observed in both groups. Results: compared with the traditional group, the bleeding, healing and operation time of the cosmetic repair group were significantly improved. After treatment, the double eyelid symmetry score was significantly improved, and the satisfaction to the cosmetic effect was significantly improved (P<0.05). Conclusion: the application of small incision liposuction combined with continuous catgut embedding double eyelid plasty can achieve good effect of double eyelid plasty with good aesthetic appearance and shortened course of treatment.
文摘An immunohistochemical study of T lymphocyte subsets on frozen substituted plastic embedding bone marrow sections obtained from 10 patients with myelodysplastic syndrome (MDS) was presented. The results of qualitative and quantitative immunohistochemical analysis are as follows: (1) Labile antigens of T lymphocytes were well preserved, thus allowing analysis of distribution of T lymphocyte subsets in situ ; (2) the average number of T 3, T 4 and T 8 lymphocyte of the diffuse infiltrate was about 2 %, 0.4 %, 0.5 %, respectively, of all nucleated cells in bone marrow, and T 4/T 8 of T cells were below 1.0 in patients with MDS; (3) there were cases of RAS showing T lymphocyte aggregation in bone marrow, but no patient exhibited progressive refractory anemia with excess of blasts(RAEB) and RAEB in transformation (RAEBT). These findings indicated that the immunological abnormalities are of importance in the evaluation of pathogenesis and prognosis of MDS.
文摘For the issue of proppant embedment in hydraulic fracturing,a new calculation method of embedment depth considering elastic-plastic deformation was proposed based on the mechanism of proppant embedment into rocks by combining proppant embedment constitutive equations and contact stresses on the rock-proppant system.And factors affecting embedment depth of proppant were analyzed using the new method.Compared with the elastic embedment model,the results calculated by the new method match well with the experimental data,proving the new method is more reliable and more convenient to make theoretical calculation and analysis.The simulation results show the process of proppant embedment into rocks is mainly elastic-plastic.The embedment depth of monolayer proppants decreases with higher proppant concentration.Under multi-layer distribution conditions,increasing the proppant concentration will not change its embedment depth.The larger the proppant embedment ratio,the more the stress-bearing proppants,and the smaller the embedment depth will be.The embedment depth under higher closure stress is more remarkable.The embedment depth increased with the drawdown of fluid pressure in the fracture.Increasing proppant radius or the ratio of proppant Young’s modulus to rock Young’s modulus can reduce the proppant embedment depth.
