Accurate ab initio-based adiabatic global potential energy surface for the 2(2)A" state of NH2 by extrapolation to the complete basis set limit.

A full three-dimensional global potential energy surface is reported first time for the title system, which is important for the photodissociation processes. It is obtained using double many-body expansion theory and an extensive set of accurate ab initio energies extrapolated to the complete basis set limit. Such a work can be recommended for dynamics studies of the N((2)D) + H2 reaction, a reliable theoretical treatment of the photodissociation dynamics and as building blocks for constructing the double many-body expansion potential energy surface of larger nitrogen/hydrogen containing systems. In turn, a preliminary theoretical study of the reaction N((2)D)+H2(X(1)Σg (+))(ν=0,j=0)→NH(a(1)Δ)+H((2)S) has been carried out with the method of quasi-classical trajectory on the new potential energy surface. Integral cross sections and thermal rate constants have been calculated, providing perhaps the most reliable estimate of the integral cross sections and the rate constants known thus far for such a reaction.

Ab initio-based double many-body expansion potential energy surface for the first excited triplet state of the ammonia molecule.

A global single-sheeted double many-body expansion potential energy surface is reported for the first excited triplet state of NH(3). It employs an approximate cluster expansion of the molecular potential that utilizes previously reported functions of the same family for the triatomic fragments. Four-body energy terms have been calibrated from extensive accurate ab initio data so as to reproduce the main features of the title system. A new switching function formalism has been reported to approximate the true multisheeted nature of NH(3)((3)A(2) ('')) potential energy surface, thus allowing the correct behavior at the NH(2)((2)A(")) + H((2)S) and NH(2)((4)A(")) + H((2)S) dissociation limits. The resulting fully six-dimensional potential energy function reproduces the correct symmetry under the permutation of identical atoms, and predicts the correct behavior at all dissociation channels while providing a realistic representation at all interatomic separations. The major attributes of the NH(3) double many-body expansion potential energy surface have also been characterized, and found to be in good agreement, both with the calculated ones from the raw ab initio energies and the theoretical results available in the literature.

Families of Chinese children with malignancy: the factors impact on mother's anxiety.

This study examines the impact of the stress experienced by mothers during a child's cancer treatment. A descriptive correlation study has been designed to examine the relationships between uncertainty, sense of mastery, boundary ambiguity, and anxiety. The sample consists of 100 mothers recruited in two teaching hospitals in Taiwan. The sense of mastery was found to act as a mediator between uncertainty and anxiety, whereas uncertainty was a good predictor of boundary ambiguity. The first 2 months of treatment and the incidence of cancer recurrence represented a significant special experience for mothers. Nursing intervention to improve the mothers' sense of mastery and to assist families in establishing functional patterns of parent-child interaction is discussed.

[An analysis of 23 cases of early primary lung cancer].

This paper analyzed the clinical characteristics and long term therapeutic effectiveness of 23 cases of early primary lung cancer, which were coincide with diagnostic criteria of the disease in our country, and selected from among 1912 cases of primary bronchogenic carcinoma in our hospital during 1976-1986. The 5 year survival rate after operation was 72.8%. We compared the detection rates of the symptomatology and some principle methods of examination in wide use between early central and peripheral types of lung cancer. This paper emphasized that the diagnosis combined with multiple discipline was of importance to early finding the diseases. In this group, the comprehensive detection rate was 77.6%. To determine early central type of lung cancer depended in large part on hemoptysis, sputum cytology and fiberoptic bronchoscopy, and to find early peripheral type of lung cancer relied entirely on chest X-ray. Some other methods finding early lung cancer were also briefly discussed.