Mepiquat chloride(1,1-dimethyl piperidinium chloride,DPC)is a representative plant growth regulator which can regulate the source-sink relationship for yield increase and shape ideal plant type for mechanical cultivat...Mepiquat chloride(1,1-dimethyl piperidinium chloride,DPC)is a representative plant growth regulator which can regulate the source-sink relationship for yield increase and shape ideal plant type for mechanical cultivation.Here we show a DPC adsorbed layered double hydroxide(DPC-LDH)architecture with enhanced controlled release property and soil distribution.By drip irrigation on cotton,it makes total dosage of DPC reduced from 270 to 90 g/ha,while the frequency decreased from 5 to 2 times.The unique supramolecular interaction is confirmed as the basis of controlled release behavior.Moreover,except for the physical resistance to the sedimentation brought by the lamellar LDH,the enhanced electrostatic interaction makes DPC-LDH the dominant distribution in soil.It improves the efficiency of DPC molecules absorbed by cotton plants and greatly saves the inputs in labor and chemicals.This method is expected to achieve the yield increase and agricultural sustainability by energy saving and emission reduction.展开更多
This paper addresses the development and testing of a remotely controlled boat platform with an innovative air-ventilated hull. The application of air cavities on the underside of ship hulls is a promising means for r...This paper addresses the development and testing of a remotely controlled boat platform with an innovative air-ventilated hull. The application of air cavities on the underside of ship hulls is a promising means for reducing hydrodynamic drag and pollutant emissions and increasing marine transportation efficiency. Despite this concept＇s potential, design optimization and high-performance operation of novel air-cavity ships remain a challenging problem. Hull construction and sensor instrumentation of the model-scale air-cavity boat is described in the paper. The modular structure of the hull allows for easy modifications, and an electric propulsion unit enables self-propelled operation. The boat is controlled remotely via a radio transmission system. Results of initial tests are reported, including thrust, speed, and airflow rate in several loading conditions. The constructed platform can be used for optimizing air-cavity systems and testing other innovative hull designs. This system can be also developed into a high-performance unmanned boat.展开更多
In this paper,we give the geometric constraint conditions of a canonical symplectic form and regular reduced symplectic forms for the dynamical vector fields of a regular controlled Hamiltonian(RCH)system and its regu...In this paper,we give the geometric constraint conditions of a canonical symplectic form and regular reduced symplectic forms for the dynamical vector fields of a regular controlled Hamiltonian(RCH)system and its regular reduced systems,which are called the Type I and Type II Hamilton-Jacobi equations.First,we prove two types of Hamilton-Jacobi theorems for an RCH system on the cotangent bundle of a configuration manifold by using the canonical symplectic form and its dynamical vector field.Second,we generalize the above results for a regular reducible RCH system with symmetry and a momentum map,and derive precisely two types of Hamilton-Jacobi equations for the regular point reduced RCH system and the regular orbit reduced RCH system.Third,we prove that the RCH-equivalence for the RCH system,and the RpCH-equivalence and RoCH-equivalence for the regular reducible RCH systems with symmetries,leave the solutions of corresponding Hamilton-Jacobi equations invariant.Finally,as an application of the theoretical results,we show the Type I and Type II Hamilton-Jacobi equations for the Rp-reduced controlled rigid body-rotor system and the Rp-reduced controlled heavy top-rotor system on the generalizations of the rotation group SO(3)and the Euclidean group SE(3),respectively.This work reveals the deeply internal relationships of the geometrical structures of phase spaces,the dynamical vector fields and the controls of the RCH system.展开更多
Pt-based nanoframes represent a class of promising catalysts towards oxygen reduction reaction. Herein, we, for the first time, successfully prepared Pt-Pd octahedral nanoframes with ultrathin ridges less than 2 nm in...Pt-based nanoframes represent a class of promising catalysts towards oxygen reduction reaction. Herein, we, for the first time, successfully prepared Pt-Pd octahedral nanoframes with ultrathin ridges less than 2 nm in thickness. The Pt-Pd octahedral nanoframes were obtained through site-selected deposition of Pt atoms onto the edge sites of Pd octahedral seeds, followed by selective removal of the Pd octahedral cores via chemical etching. Due to that a combination of three-dimensional opens geometrical structure and Pt-skin surface compositional structure, the Pt-Pd octahedral nanoframes/C catalyst shows a mass activity of 1.15 A/mgPt towards oxygen reduction reaction, 5.8 times enhancement in mass activity relative to commercial Pt/C catalyst （0.20 A/mgPt）. Moreover, even after 8000 cycles of accelerated durability test, the Pt-Pd octahedral nanoframes/C catalyst still exhibits a mass activity which is more than three times higher than that of pristine Pt/C catalyst.展开更多
Aim: Common treatment options for obesity include a reduced-calorie diet, increased physical activity, behavioral modification, pharmacotherapy, and surgery. Ear acupressure may also be an effective adjunct therapy. M...Aim: Common treatment options for obesity include a reduced-calorie diet, increased physical activity, behavioral modification, pharmacotherapy, and surgery. Ear acupressure may also be an effective adjunct therapy. Methods: This study used a randomized controlled design to test the effectiveness of auricular acupressure for weight reduction in young, Taiwan Residents adults with a BMI ≥ 23 kg/m2. Sixty-eight participants aged 18 to 20 years were recruited from Taiwan Residents universities at the beginning of the study. After four weeks of auricular therapy, the total sample included 57 young adults. All participants met one time per week for ten minutes. The treatment group received ear acupressure treatment with Semen Vaccariae sticks on auricular acupoints while the control group had adhesive tape placed on ear acupoints, change in BMI from baseline to trial completion. Results: BMI in controls increased significantly by +0.0133 kg/m2 (P = 0.000) while the intervention group BMI decreased significantly by ?0.8022 kg/m2 (P ≤ 0.0001). Conclusions: Just four weeks of auricular acupressure by Semen Vaccariae, sticks may significantly help to decrease BMI among young adults.展开更多
.As an application of the theoretical results,in this paper,we study the symmetric reduction and Hamilton-Jacobi theory for the underwater ve-hicle with two internal rotors as a regular point reducible RCH system,in t....As an application of the theoretical results,in this paper,we study the symmetric reduction and Hamilton-Jacobi theory for the underwater ve-hicle with two internal rotors as a regular point reducible RCH system,in the cases of coincident and non-coincident centers of the buoyancy and the gravity.At first,we give the regular point reduction and the two types of Hamilton-Jacobi equations for a regular controlled Hamiltonian(RCH)system with sym-metry and a momentum map on the generalization of a semidirect product Lie group.Next,we derive precisely the geometric constraint conditions of the reduced symplectic forms for the dynamical vector fields of the regular point reducible controlled underwater vehicle-rotor system,that is,the two types of Hamilton-Jacobi equations for the reduced controlled underwater vehicle-rotor system,by calculations in detail.These work reveal the deeply internal relationships of the geometrical structures of the phase spaces,the dynamical vector fields and the controls of the system.展开更多
基金supported by the National Key R&D Program of China(2021YFA0716704)the Young Scientists Fund of the National Natural Science Foundation of China(No.22208372).
文摘Mepiquat chloride(1,1-dimethyl piperidinium chloride,DPC)is a representative plant growth regulator which can regulate the source-sink relationship for yield increase and shape ideal plant type for mechanical cultivation.Here we show a DPC adsorbed layered double hydroxide(DPC-LDH)architecture with enhanced controlled release property and soil distribution.By drip irrigation on cotton,it makes total dosage of DPC reduced from 270 to 90 g/ha,while the frequency decreased from 5 to 2 times.The unique supramolecular interaction is confirmed as the basis of controlled release behavior.Moreover,except for the physical resistance to the sedimentation brought by the lamellar LDH,the enhanced electrostatic interaction makes DPC-LDH the dominant distribution in soil.It improves the efficiency of DPC molecules absorbed by cotton plants and greatly saves the inputs in labor and chemicals.This method is expected to achieve the yield increase and agricultural sustainability by energy saving and emission reduction.
基金Foundation item： Supported by the National Science Foundation （CMMI-1026264 and EEC-1157094）.
文摘This paper addresses the development and testing of a remotely controlled boat platform with an innovative air-ventilated hull. The application of air cavities on the underside of ship hulls is a promising means for reducing hydrodynamic drag and pollutant emissions and increasing marine transportation efficiency. Despite this concept＇s potential, design optimization and high-performance operation of novel air-cavity ships remain a challenging problem. Hull construction and sensor instrumentation of the model-scale air-cavity boat is described in the paper. The modular structure of the hull allows for easy modifications, and an electric propulsion unit enables self-propelled operation. The boat is controlled remotely via a radio transmission system. Results of initial tests are reported, including thrust, speed, and airflow rate in several loading conditions. The constructed platform can be used for optimizing air-cavity systems and testing other innovative hull designs. This system can be also developed into a high-performance unmanned boat.
基金partially supported by the Nankai University 985 Projectthe Key Laboratory of Pure Mathematics and Combinatorics,Ministry of Education,Chinathe NSFC(11531011)。
文摘In this paper,we give the geometric constraint conditions of a canonical symplectic form and regular reduced symplectic forms for the dynamical vector fields of a regular controlled Hamiltonian(RCH)system and its regular reduced systems,which are called the Type I and Type II Hamilton-Jacobi equations.First,we prove two types of Hamilton-Jacobi theorems for an RCH system on the cotangent bundle of a configuration manifold by using the canonical symplectic form and its dynamical vector field.Second,we generalize the above results for a regular reducible RCH system with symmetry and a momentum map,and derive precisely two types of Hamilton-Jacobi equations for the regular point reduced RCH system and the regular orbit reduced RCH system.Third,we prove that the RCH-equivalence for the RCH system,and the RpCH-equivalence and RoCH-equivalence for the regular reducible RCH systems with symmetries,leave the solutions of corresponding Hamilton-Jacobi equations invariant.Finally,as an application of the theoretical results,we show the Type I and Type II Hamilton-Jacobi equations for the Rp-reduced controlled rigid body-rotor system and the Rp-reduced controlled heavy top-rotor system on the generalizations of the rotation group SO(3)and the Euclidean group SE(3),respectively.This work reveals the deeply internal relationships of the geometrical structures of phase spaces,the dynamical vector fields and the controls of the RCH system.
基金This work is supported by Collaborative Innovation Center of Suzhou Nano Science and Technology, Ministry of Science and Technology of China （No.2014CB932700）, the National Natural Science Foundation of China （No.21603208, No.21573206, and No.51371164）, the China Postdoctoral Science Foundation （No.2015M580536, No.2016T90569）, Key Research Program of Frontier Sciences, CAS （QYZDBSSW- SLH017）, Strategic Priority Research Program B of the CAS （No.XDB01020000）, Hefei Science Center, CAS （No.2015HSC-UP016）, and Fundamental Research Funds for the Central Universities.
文摘Pt-based nanoframes represent a class of promising catalysts towards oxygen reduction reaction. Herein, we, for the first time, successfully prepared Pt-Pd octahedral nanoframes with ultrathin ridges less than 2 nm in thickness. The Pt-Pd octahedral nanoframes were obtained through site-selected deposition of Pt atoms onto the edge sites of Pd octahedral seeds, followed by selective removal of the Pd octahedral cores via chemical etching. Due to that a combination of three-dimensional opens geometrical structure and Pt-skin surface compositional structure, the Pt-Pd octahedral nanoframes/C catalyst shows a mass activity of 1.15 A/mgPt towards oxygen reduction reaction, 5.8 times enhancement in mass activity relative to commercial Pt/C catalyst （0.20 A/mgPt）. Moreover, even after 8000 cycles of accelerated durability test, the Pt-Pd octahedral nanoframes/C catalyst still exhibits a mass activity which is more than three times higher than that of pristine Pt/C catalyst.
文摘Aim: Common treatment options for obesity include a reduced-calorie diet, increased physical activity, behavioral modification, pharmacotherapy, and surgery. Ear acupressure may also be an effective adjunct therapy. Methods: This study used a randomized controlled design to test the effectiveness of auricular acupressure for weight reduction in young, Taiwan Residents adults with a BMI ≥ 23 kg/m2. Sixty-eight participants aged 18 to 20 years were recruited from Taiwan Residents universities at the beginning of the study. After four weeks of auricular therapy, the total sample included 57 young adults. All participants met one time per week for ten minutes. The treatment group received ear acupressure treatment with Semen Vaccariae sticks on auricular acupoints while the control group had adhesive tape placed on ear acupoints, change in BMI from baseline to trial completion. Results: BMI in controls increased significantly by +0.0133 kg/m2 (P = 0.000) while the intervention group BMI decreased significantly by ?0.8022 kg/m2 (P ≤ 0.0001). Conclusions: Just four weeks of auricular acupressure by Semen Vaccariae, sticks may significantly help to decrease BMI among young adults.
文摘.As an application of the theoretical results,in this paper,we study the symmetric reduction and Hamilton-Jacobi theory for the underwater ve-hicle with two internal rotors as a regular point reducible RCH system,in the cases of coincident and non-coincident centers of the buoyancy and the gravity.At first,we give the regular point reduction and the two types of Hamilton-Jacobi equations for a regular controlled Hamiltonian(RCH)system with sym-metry and a momentum map on the generalization of a semidirect product Lie group.Next,we derive precisely the geometric constraint conditions of the reduced symplectic forms for the dynamical vector fields of the regular point reducible controlled underwater vehicle-rotor system,that is,the two types of Hamilton-Jacobi equations for the reduced controlled underwater vehicle-rotor system,by calculations in detail.These work reveal the deeply internal relationships of the geometrical structures of the phase spaces,the dynamical vector fields and the controls of the system.
