The crystal structure, magnetic and magnetocaloric properties of(Ho_(1-x) Y_(0.5))_5 Pd_2 compounds are investigated. All the compounds crystallize in a cubic Dy_5 Pd_2-type structure with the space group Fd3 m and un...The crystal structure, magnetic and magnetocaloric properties of(Ho_(1-x) Y_(0.5))_5 Pd_2 compounds are investigated. All the compounds crystallize in a cubic Dy_5 Pd_2-type structure with the space group Fd3 m and undergo a second order transition from spin glass(SG) state to paramagnetic(PM) state. The spin glass transition temperatures T_g decrease from 26 K for x = 0 to 13 K for x = 0.5. In the PM region, the reciprocal susceptibilities for all the compounds obey the Curie–Weiss law. The paramagnetic Curie temperatures(θp) for Ho_5 Pd_2,(Ho_(0.75) Y_(0.25)_5 Pd_2, and(Ho_(0.5) Y_(0.5))_5 Pd_2 are determined to be 32 K, 30 K, and 22 K, respectively, and the corresponding effective magnetic moments(μeff) are10.8 μB/Ho, 10.3 μB/RE, and 7.5 μB/RE, respectively. Magnetocaloric effect(MCE) is anticipated according to the Maxwell relation, based on the isothermal magnetization curves. For a magnetic field change of 0–5 T, the maximum values of the isothermal magnetic entropy change-?SMof the(Ho_(1-x)Y_x)_5 Pd_2(x = 0, 0.25, and 0.5) compounds are determined to be 11.5 J·kg^(-1)·K^(-1), 11.1 J·kg^(-1)·K^(-1), and 8.9 K J·kg^(-1)·K^(-1), with corresponding refrigerant capacity values of 382.3 J·kg^(-1), 336.2 J·kg^(-1), and 242.5 J·kg^(-1), respectively.展开更多
免疫治疗在肿瘤治疗中占据着重要地位,已知T细胞表面的程序性死亡受体-1(programmed death receptor-1,PD-1)与肿瘤细胞上的PD-1配体1(PD-1 ligand 1,PD-L1)结合可以阻止T细胞对肿瘤细胞的免疫杀伤作用,促进肿瘤细胞的免疫逃逸。本文围...免疫治疗在肿瘤治疗中占据着重要地位,已知T细胞表面的程序性死亡受体-1(programmed death receptor-1,PD-1)与肿瘤细胞上的PD-1配体1(PD-1 ligand 1,PD-L1)结合可以阻止T细胞对肿瘤细胞的免疫杀伤作用,促进肿瘤细胞的免疫逃逸。本文围绕PD-1/PD-L1抑制剂介绍了其在结直肠癌治疗中存在的问题,结直肠癌中PI3K/AKT、JAK/STAT、MAPK、NF-κB等信号通路与PD-1/PD-L1的相互作用机制,进一步探讨了PD-1/PD-L1抑制剂与肠道微生物、化疗、放疗、靶向和天然化合物的治疗研究。展开更多
A novel 0.1% Pd-0.05% （mass fraction） Pt/stainless steel wire mesh catalyst was prepared for volatile organic compounds （VOCs） elimination. The catalyst was synthesized by stainless steel wire mesh as support and ...A novel 0.1% Pd-0.05% （mass fraction） Pt/stainless steel wire mesh catalyst was prepared for volatile organic compounds （VOCs） elimination. The catalyst was synthesized by stainless steel wire mesh as support and then treated by anodic oxidation technology to develop a porous membrane on the support. During the anodic oxidation process, various electrolytes were used to investigate the formation of porous membrane. And the catalytic performance of the catalysts was tested by using toluene and acetone combustion as model reaction. The temperatures of complete toluene and acetone conversion were decreased to 180℃ and 240 ℃, respectively. The morphologies of the stainless steel wire mesh supports and catalysts were characterized by means of scanning electron microscopy （SEM） and temperature-programmed reduction （TPR）.展开更多
The crystal structure of the title compound was determined, Mr =424. 47, orthorhombic, Pbca, a= 20. 780(5), b= 8. 601 (3), c= 8. 285(3) A, V=1480. 8(5) A, Z=4, Dc= 1. 904 g/cm3, μ(MoKa) = 19. 59 cm-1, F(000)=848.The ...The crystal structure of the title compound was determined, Mr =424. 47, orthorhombic, Pbca, a= 20. 780(5), b= 8. 601 (3), c= 8. 285(3) A, V=1480. 8(5) A, Z=4, Dc= 1. 904 g/cm3, μ(MoKa) = 19. 59 cm-1, F(000)=848.The final R =0. 038, Rw=0.063 for 1554 independent observed reflections (I> 3σ(I) ). The crystal contains an isolated [PdCl4]2- planar tetragon and two morpholiniumcations which are linked to the anion ed N -H...Cl hydrogen bonds with donor-acceptor distances of 3. 394 and 3. 399 A, respectively.展开更多
The crystal structures and magnetic properties of novel Eu TrGa3-r （T=Pd, It, Rh） in termetallic compounds are investigated by using powder x-ray diffraction and magnetic measurements. EuTrGa3-r crystallizes in orth...The crystal structures and magnetic properties of novel Eu TrGa3-r （T=Pd, It, Rh） in termetallic compounds are investigated by using powder x-ray diffraction and magnetic measurements. EuTrGa3-r crystallizes in orthorhombic structure with space group of Cmcm and Z = 4. There are four kinds of nonequivalent 4c crystal positions in EuTrGaa-r unit cell, which are occupied by 4Eu, 4GaⅠ, 4（GaⅡ, T） and 4GaⅢ, respectively. EuTrGa3-r ex- hibits the complex magnetic states in low-temperature regime, with the three-, two- and one-antiferromagnetic transitions occurring for T=Ir, T=Rh and T=Pd, respectively. It might be due to the Kondo effect： a localized antiferromagnetic interaction of the isolated impurity spins with the surrounding conduction electrons at low-temperature regime.展开更多
利用基于密度泛函理论(DFT)的第一性原理研究了O原子与Pd掺杂前后ZnO(0001)表面的相互作用机理。通过对模型表面六个高对称位吸附能的计算,发现O原子最有可能吸附于Pd掺杂表面的间隙位。从表面的态密度(density of states,DOS)及分波态...利用基于密度泛函理论(DFT)的第一性原理研究了O原子与Pd掺杂前后ZnO(0001)表面的相互作用机理。通过对模型表面六个高对称位吸附能的计算,发现O原子最有可能吸附于Pd掺杂表面的间隙位。从表面的态密度(density of states,DOS)及分波态密度(partial density of states,PDOS)分析结果可以看出,掺杂体系中费米能级附近出现的杂化峰是由O原子的p轨道电子和Pd原子的d轨道电子杂化引起的。掺杂表面的差分电荷密度反映出O原子与Pd原子之间存在大量电荷转移,说明掺入催化剂Pd有助于提高ZnO材料的气敏性能。最后,通过对挥发性有机化合物(VOC)气体的气敏测试验证了理论计算的结论。展开更多
基金Project supported by the National Basic Research Program of China(Grant No.2014CB643703)the National Key Research and Development Program of China(Grant No.2016YFB0700901)+1 种基金the National Natural Science Foundation of China(Grant Nos.51261004 and 51761007)Guangxi Natural Science Foundation,China(Grant No.2018GXNSFAA294051)
文摘The crystal structure, magnetic and magnetocaloric properties of(Ho_(1-x) Y_(0.5))_5 Pd_2 compounds are investigated. All the compounds crystallize in a cubic Dy_5 Pd_2-type structure with the space group Fd3 m and undergo a second order transition from spin glass(SG) state to paramagnetic(PM) state. The spin glass transition temperatures T_g decrease from 26 K for x = 0 to 13 K for x = 0.5. In the PM region, the reciprocal susceptibilities for all the compounds obey the Curie–Weiss law. The paramagnetic Curie temperatures(θp) for Ho_5 Pd_2,(Ho_(0.75) Y_(0.25)_5 Pd_2, and(Ho_(0.5) Y_(0.5))_5 Pd_2 are determined to be 32 K, 30 K, and 22 K, respectively, and the corresponding effective magnetic moments(μeff) are10.8 μB/Ho, 10.3 μB/RE, and 7.5 μB/RE, respectively. Magnetocaloric effect(MCE) is anticipated according to the Maxwell relation, based on the isothermal magnetization curves. For a magnetic field change of 0–5 T, the maximum values of the isothermal magnetic entropy change-?SMof the(Ho_(1-x)Y_x)_5 Pd_2(x = 0, 0.25, and 0.5) compounds are determined to be 11.5 J·kg^(-1)·K^(-1), 11.1 J·kg^(-1)·K^(-1), and 8.9 K J·kg^(-1)·K^(-1), with corresponding refrigerant capacity values of 382.3 J·kg^(-1), 336.2 J·kg^(-1), and 242.5 J·kg^(-1), respectively.
文摘免疫治疗在肿瘤治疗中占据着重要地位,已知T细胞表面的程序性死亡受体-1(programmed death receptor-1,PD-1)与肿瘤细胞上的PD-1配体1(PD-1 ligand 1,PD-L1)结合可以阻止T细胞对肿瘤细胞的免疫杀伤作用,促进肿瘤细胞的免疫逃逸。本文围绕PD-1/PD-L1抑制剂介绍了其在结直肠癌治疗中存在的问题,结直肠癌中PI3K/AKT、JAK/STAT、MAPK、NF-κB等信号通路与PD-1/PD-L1的相互作用机制,进一步探讨了PD-1/PD-L1抑制剂与肠道微生物、化疗、放疗、靶向和天然化合物的治疗研究。
基金Project(2009C21001)supported by the Science and Technology Program of Zhejiang Province,China
文摘A novel 0.1% Pd-0.05% （mass fraction） Pt/stainless steel wire mesh catalyst was prepared for volatile organic compounds （VOCs） elimination. The catalyst was synthesized by stainless steel wire mesh as support and then treated by anodic oxidation technology to develop a porous membrane on the support. During the anodic oxidation process, various electrolytes were used to investigate the formation of porous membrane. And the catalytic performance of the catalysts was tested by using toluene and acetone combustion as model reaction. The temperatures of complete toluene and acetone conversion were decreased to 180℃ and 240 ℃, respectively. The morphologies of the stainless steel wire mesh supports and catalysts were characterized by means of scanning electron microscopy （SEM） and temperature-programmed reduction （TPR）.
文摘The crystal structure of the title compound was determined, Mr =424. 47, orthorhombic, Pbca, a= 20. 780(5), b= 8. 601 (3), c= 8. 285(3) A, V=1480. 8(5) A, Z=4, Dc= 1. 904 g/cm3, μ(MoKa) = 19. 59 cm-1, F(000)=848.The final R =0. 038, Rw=0.063 for 1554 independent observed reflections (I> 3σ(I) ). The crystal contains an isolated [PdCl4]2- planar tetragon and two morpholiniumcations which are linked to the anion ed N -H...Cl hydrogen bonds with donor-acceptor distances of 3. 394 and 3. 399 A, respectively.
基金Supported by the National Natural Science Foundation of China under Grant No 11274110
文摘The crystal structures and magnetic properties of novel Eu TrGa3-r （T=Pd, It, Rh） in termetallic compounds are investigated by using powder x-ray diffraction and magnetic measurements. EuTrGa3-r crystallizes in orthorhombic structure with space group of Cmcm and Z = 4. There are four kinds of nonequivalent 4c crystal positions in EuTrGaa-r unit cell, which are occupied by 4Eu, 4GaⅠ, 4（GaⅡ, T） and 4GaⅢ, respectively. EuTrGa3-r ex- hibits the complex magnetic states in low-temperature regime, with the three-, two- and one-antiferromagnetic transitions occurring for T=Ir, T=Rh and T=Pd, respectively. It might be due to the Kondo effect： a localized antiferromagnetic interaction of the isolated impurity spins with the surrounding conduction electrons at low-temperature regime.
基金supported by the National Natural Science Foundation of China(21173153)National Hi-tech Research and Development Program of China(863)(2015AA034603)Opening Project of Key Laboratory of Green Chemistry of Sichuan Institutes of Higher Education,China(LYJ1407)~~
文摘利用基于密度泛函理论(DFT)的第一性原理研究了O原子与Pd掺杂前后ZnO(0001)表面的相互作用机理。通过对模型表面六个高对称位吸附能的计算,发现O原子最有可能吸附于Pd掺杂表面的间隙位。从表面的态密度(density of states,DOS)及分波态密度(partial density of states,PDOS)分析结果可以看出,掺杂体系中费米能级附近出现的杂化峰是由O原子的p轨道电子和Pd原子的d轨道电子杂化引起的。掺杂表面的差分电荷密度反映出O原子与Pd原子之间存在大量电荷转移,说明掺入催化剂Pd有助于提高ZnO材料的气敏性能。最后,通过对挥发性有机化合物(VOC)气体的气敏测试验证了理论计算的结论。
