The Gender Education Gap in China: The Power of Water

We investigate girls' school dropout rates, bringing forward a novel variable: access to water. We hypothesise that a girl's education suffers when her greater water need for female hygiene purposes after menarche is not met because her household has poor access to water. For testing we use data from rural villages in the China Health and Nutrition Survey. We find that menarche is associated with an increase in the school dropout rate, and indeed the effect is weaker for girls who have good access to water. Water engineering can thus contribute significantly to reducing gender education gaps in rural areas.education, gender gaps, menarche, water, China

Wage Work for Women: The Menstrual Cycle and the Power of Water

We hypothesise that women's participation in wage (off-farm) work is reduced when their greater water needs due to the menstrual cycle are not met because their household has poor access to water. For testing, we use the data from rural villages in China. Controlling for village fixed effects, poor access to water is found to decrease the probability of wage work participation of affected (pre-menopause) women by about 10 percentage points, a large effect. As expected, there is no adverse causal impact of poor household access to water for women post-menopause, or for men, ceteris paribus.wage work, women, menopause, water engineering, rural development, China

Kinetics and coverage dependent reaction mechanisms of the copper atomic layer deposition from copper dimethylamino-2-propoxide and diethylzinc

Atomic layer deposition (ALD) has been recognized as a promising method to deposit conformal and uniform thin film of copper for future electronic devices. However, many aspects of the reaction mechanism and the surface chemistry of copper ALD remain unclear. In this paper, we employ plane wave density functional theory (DFT) to study the transmetalation ALD reaction of copper dimethylamino-2-propoxide [Cu(dmap)2] and diethylzinc [Et2Zn] that was realized experimentally by Lee et al. [ Angew. Chem., Int. Ed. 2009, 48, 4536−4539]. We find that the Cu(dmap)2 molecule adsorbs and dissociates through the scission of one or two Cu–O bonds into surface-bound dmap and Cu(dmap) fragments during the copper pulse. As Et2Zn adsorbs on the surface covered with Cu(dmap) and dmap fragments, butane formation and desorption was found to be facilitated by the surrounding ligands, which leads to one reaction mechanism, while the migration of ethyl groups to the surface leads to another reaction mechanism. During both reaction mechanisms, ligand diffusion and reordering are generally endothermic processes, which may result in residual ligands blocking the surface sites at the end of the Et2Zn pulse, and in residual Zn being reduced and incorporated as an impurity. We also find that the nearby ligands play a cooperative role in lowering the activation energy for formation and desorption of byproducts, which explains the advantage of using organometallic precursors and reducing agents in Cu ALD. The ALD growth rate estimated for the mechanism is consistent with the experimental value of 0.2 Å/cycle. The proposed reaction mechanisms provide insight into ALD processes for copper and other transition metals

Computational study of the growth of copper thin films by atomic layer deposition

Copper is the main interconnect material in microelectronic devices, and a 2 nm-thick continuous Cu film seed layer needs to be deposited to produce microelectronic devices with the smallest features and more functionality. Atomic layer deposition (ALD) is the most suitable method to deposit such thin films. However, the reaction mechanism and the surface chemistry of copper ALD remain unclear, which is deterring the development of better precursors and design of new ALD processes. In this thesis, we study the surface chemistries during ALD of copper by means of density functional theory (DFT). To understand the effect of temperature and pressure on the composition of copper with substrates, we used ab initio atomistic thermodynamics to obtain phase diagram of the Cu(111)/SiO2(0001) interface. We found that the interfacial oxide Cu2O phases prefer high oxygen pressure and low temperature while the silicide phases are stable at low oxygen pressure and high temperature for Cu/SiO2 interface, which is in good agreement with experimental observations. Understanding the precursor adsorption on surfaces is important for understanding the surface chemistry and reaction mechanism of the Cu ALD process. Focusing on two common Cu ALD precursors, Cu(dmap)2 and Cu(acac)2, we studied the precursor adsorption on Cu surfaces by means of van der Waals (vdW) inclusive DFT methods. We found that the adsorption energies and adsorption geometries are dependent on the adsorption sites and on the method used to include vdW in the DFT calculation. Both precursor molecules are partially decomposed and the Cu cations are partially reduced in their chemisorbed structure. It is found that clean cleavage of the ligand−metal bond is one of the requirements for selecting precursors for ALD of metals. 2 Bonding between surface and an atom in the ligand which is not coordinated with the Cu may result in impurities in the thin film. To have insight into the reaction mechanism of a full ALD cycle of Cu ALD, we proposed reaction pathways based on activation energies and reaction energies for a range of surface reactions between Cu(dmap)2 and Et2Zn. The butane formation and desorption steps are found to be extremely exothermic, explaining the ALD reaction scheme of original experimental work. Endothermic ligand diffusion and re-ordering steps may result in residual dmap ligands blocking surface sites at the end of the Et2Zn pulse, and in residual Zn being reduced and incorporated as an impurity. This may lead to very slow growth rate, as was the case in the experimental work. By investigating the reduction of CuO to metallic Cu, we elucidated the role of the reducing agent in indirect ALD of Cu. We found that CuO bulk is protected from reduction during vacuum annealing by the CuO surface and that H2 is required in order to reduce that surface, which shows that the strength of reducing agent is important to obtain fully reduced metal thin films during indirect ALD processes. Overall, in this thesis, we studied the surface chemistries and reaction mechanisms of Cu ALD processes and the nucleation of Cu to form a thin film

HRM Practices and Performance of Family-Run Workplaces: Evidence from the 2004 WERS

This paper analyses HRM practices of family-run workplaces using the 2004 WERS. Family-ownership and management within workplaces in the corporate sector is our focus. This family-run group represents nationally about 26% of workplaces and 14% of employment. We find that employees in this group have stronger feelings of job security and loyalty, which we relate to family companies' HRM practices such as stronger support for long-term employment – an "inclusivity" linked to long-term orientation. We also find that family-owned and managed workplaces have better financial and quality performance measures than non-family, to which family-related HRM practices contribute.job security, loyalty, family business, HRM practices, financial performance

Classification of processes for the atomic layer deposition of metals based on mechanistic information from density functional theory calculations

Reaction cycles for the atomic layer deposition (ALD) of metals are presented, based on the incomplete data that exist about their chemical mechanisms, particularly from density functional theory (DFT) calculations. ALD requires self-limiting adsorption of each precursor, which results from exhaustion of adsorbates from previous ALD pulses and possibly from inactivation of the substrate through adsorption itself. Where the latter reaction does not take place, an “abbreviated cycle” still gives self-limiting ALD, but at a much reduced rate of deposition. Here, for example, ALD growth rates are estimated for abbreviated cycles in H2-based ALD of metals. A wide variety of other processes for the ALD of metals are also outlined and then classified according to which a reagent supplies electrons for reduction of the metal. Detailed results on computing the mechanism of copper ALD by transmetallation are summarized and shown to be consistent with experimental growth rates. Potential routes to the ALD of other transition metals by using complexes of non-innocent diazadienyl ligands as metal sources are also evaluated using DFT

Reduction mechanisms of the CuO(111) surface through surface oxygen vacancy formation and hydrogen adsorption

We studied the reduction of CuO(111) surface using density functional theory (DFT) with the generalized gradient approximation corrected for on-site Coulomb interactions (GGA + U) and screened hybrid DFT (HSE06 functional). The surface reduction process by oxygen vacancy formation and H2 adsorption on the CuO(111) surface is investigated as two different reduction mechanisms. It is found that both GGA + U and HSE06 predict the same trend in the relative stability of oxygen vacancies. We found that loss of the subsurface oxygen is initially thermodynamically favourable. As the oxygen vacancy concentration increases, mixture of subsurface and surface vacancies is energetically preferred over full reduction of the surface or subsurface monolayer. The reduction of Cu2+ to Cu+ is found to be more favourable than that of Cu+ to Cu0 in the most stable vacancy structures at all concentrations. Consistent with the oxygen vacancy calculations, H2 adsorption occurs initially on under-coordinated surface oxygen. Water molecules are formed upon the adsorption of H2 and this gives a mechanism for H2 reduction of CuO to Cu. Ab initio atomistic thermodynamics shows that reducing CuO to metallic Cu at the surface is more energetically difficult than in the bulk so that the surface oxide protects the bulk from reduction. Using H2 as the reducing agent, it is found that the CuO surface is reduced to Cu2O at approximately 360 K and that complete reduction from Cu2O to metallic Cu occurs at 780 K

Training, education and productivity

This paper investigates the impact of training and education on productivity, in particular linking to a literature that emphasizes the need to reorganise production following adoption of ICT. The paper examines training at the total economy level and variation across industries, focusing especially on manufacturing versus market service sectors. It also examines the characteristics of those who receive training and outlines the incentives that underlie this

Training, education and productivity

This paper investigates the impact of training and education on productivity, in particular linking to a literature that emphasizes the need to reorganise production following adoption of ICT. The paper examines training at the total economy level and variation across industries, focusing especially on manufacturing versus market service sectors. It also examines the characteristics of those who receive training and outlines the incentives that underlie this

Women’s education and work in China: the menstrual cycle and the power of water

This study investigates the joint impact of menstrual cycle and poor access to water on women’s education and labour market outcomes. The research context is chosen to be rural China. Two parallel hypotheses that are tested in this study are as follows: (1) Girls have less probability of school enrolment and shorter schooling duration due to the joint impact of poor access to water and menarche presumably because that poor access to water may raise time/health/psychic costs of school enrolment for girls post-menarche. (2) Women have less probability of participating in work for wages due to the joint impact of poor access to water and menstrual cycle presumably because that poor access to water may generate lower productivity and raise time/health/psychic costs of wage work participation for women pre-menopause. For testing, the researcher uses the data from rural villages in the China Health and Nutrition Survey. This study conducts two sets of empirical tests on each of the above hypotheses using regression models and propensity score matching estimators. It is found that the joint impact of poor access to water and menstrual cycle is indeed largely adverse on women’s education and wage work participation. When the impacts of other confounding factors such as poverty and backward geographical location are controlled for, access to poor water is found to decrease the probability of school enrolment of post-menarche girls by 20 – 25 percentage points, and the probability of wage work participation of women premenopause by about 10 percentage points. This study concludes that a major benefit of policies to improve water supplies may not be the obvious household or industrial benefit, but rather an unseen benefit, the improvement in the position of wome