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BackgroundWe have reported both perceived benefits and harms of the COVID-19 outbreak and their socioeconomic disparities amid the pandemic in Hong Kong. We further investigated whether such perceptions and disparities had changed after 10 months.MethodsUnder the Hong Kong Jockey Club SMART Family-Link Project, we conducted two cross-sectional surveys online on perceived personal and family benefits and harms of the COVID-19 outbreak in Hong Kong adults in May 2020 (after Wave 2 was under control; N = 4,891) and in February and March 2021 (after Wave 4 was under control; N = 6,013). We collected sociodemographic information, including sex, age, education, household income, and housing. Using multivariate models of analysis of covariance (MANCOVA), we compared perceived benefits and harms and socioeconomic disparities between the two surveys.ResultsAdjusting for sex and age, the prevalence of 17 out of 18 perceived personal and family benefits of COVID-19 outbreak increased (Ps < 0.001). Six of 11 perceived personal and family harms decreased (Ps < 0.001) and 4 increased (Ps < 0.001). The total number of perceived personal and family benefits increased substantially (Ps < 0.001), whereas that of perceived personal harms decreased (P = 0.01) and family harms remained stable (P > 0.05). Socioeconomic disparities, however, persisted—more perceived benefits in those with higher socioeconomic status (Ps < 0.001) and more perceived harms in those with lower (Ps ≤ 0.005).ConclusionWe have first reported that perceived personal and family benefits of the COVID-19 outbreak increased substantially over 10 months amid the pandemic, while perceived personal and family harms were lower and stable, respectively. Socioeconomic disparities of the perceived benefits and harms persisted, which need to be monitored and addressed urgently.

Background Adversity coping capability (ACC) is important amid the COVID-19 pandemic. We examined the associations of ACC as measured by our one-item ACC scale (ACC-1) with mental health, family well-being and validity of ACC-1 in Hong Kong. Methods A cross-sectional survey was conducted on Hong Kong Chinese adults aged ≥ 18 years by landline, mobile phone, and online survey from February to March 2021, when the fourth wave of COVID-19 was under control. ACC-1 consisted of the question: “How do you rate your capability to cope with adversities?” with higher scores (0–10) indicating stronger ACC. The associations of ACC with socioeconomic characteristics, resilience, mental health, and family wellbeing were examined by linear regression coefficients (βs). Data were weighted by sex, age, and education of the general population. Results Of 7441 respondents, after weighing, 52.2% were female and 79.1% were aged 18 to 64 years. ACC-1 showed good construct validity, with higher ACC being associated with higher levels of resilience (adjusted β = 0.29), personal happiness (0.55), family happiness (0.42), family wellbeing (0.41), and family communication quality (0.41), and lower levels of depressive symptoms (-0.30), anxiety (-0.30), loneliness (-0.15); incremental validity with additional contributions of ACC to mental health and family wellbeing; and known-group validity with older age and favorable socioeconomic characteristics showing higher ACC (all P P ≤ 0.02). Conclusions We have first shown that stronger ACC was associated with better mental health and family wellbeing, and the results support ACC-1 as a simple and valid measure of ACC.

BackgroundBoth face-to-face and instant messaging (IM) communication are important for families, but face-to-face communication has reduced amidst the COVID-19 pandemic. We examined the use and contents of both communication methods amidst the pandemic, their associations with family wellbeing and personal happiness, and the mediation effects of communication quality in Hong Kong Chinese adults.MethodsThis population-based online survey enrolled 4,921 respondents in May 2020, who reported (i) any face-to-face or IM family communication when the pandemic was severe; (ii) communication contents being classified as neutral, positive, supportive, and negative; and (iii) communication quality, family wellbeing and personal happiness (score 0–10). Associations of family wellbeing and personal happiness with communication methods and contents (no communication excluded) were examined using linear regressions (β), adjusting for each other, sex, age, socioeconomic status, and the number of cohabitants. Mediating effects of communication quality on these associations were examined. Prevalence estimates were weighted by sex, age, and education of the general population. Interactions of methods and contents were examined.ResultsOf 4,891 included respondents (female: 52.9%, 45–54 years: 37.7%, ≥65 years: 21.3%), 7.1% reported no communication, 12.7% face-to-face communication only, 26.7% IM only, and 53.4% both methods. More males and those at younger ages, had lower socioeconomic status, or fewer cohabitants showed no family communication or face-to-face only. More respondents reported neutral (83.1–99.3%) than positive (42.1–62.2%), supportive (37.5–54.8%), and negative (10.9–34.5%) contents despite communication methods. Communication quality was higher with both methods than IM only, face-to-face only, and no communication (scores: 6.7 vs. 4.5–6.6, all P ≤ 0.02). Better family wellbeing and personal happiness were associated with using IM only (adjusted βs: 0.37 and 0.48) and both methods (0.37 and 0.42) than face-to-face only, and positive (0.62 and 0.74) or supportive (0.45 and 0.46) contents (all P ≤ 0.001). Communication quality mediated 35.2–93.5% of these associations. Stronger associations between positive contents and family wellbeing showed in both methods and face-to-face only than IM only (P for interaction = 0.006).ConclusionsWe have first shown that, amidst the COVID-19 pandemic, family IM communication and positive and supportive contents may promote family wellbeing and personal happiness. People with no family communication may need assistance.

The COVID-19 pandemic caused different types of harms and benefits, but the combined patterns of perceived harms and benefits are unclear. We aimed to identify the patterns of perceived harms and benefits of the COVID-19 outbreak and to examine their associations with socio-demographic characteristics, happiness, and changes in smoking and drinking. A population-based cross-sectional online survey was conducted in May 2020 on Hong Kong adults (N = 4520). Patterns of perceived harms and benefits of COVID-19 were identified using latent profile analysis. Their associations with socio-demographic characteristics, happiness, and changes in smoking and drinking were examined using multinomial logistic regression. We identified three distinct patterns: indifferent (66.37%), harm (13.28%), and benefit (20.35%). Compared with the indifferent subgroup, the harm subgroup was younger, less happy, and had increased drinking, and hence might be at higher risk, whereas the benefit subgroup was more likely to be female, live with one or more cohabitants, have postsecondary education, be happier, and have decreased drinking, and could be more adaptive. Future studies can target the harm subgroup to facilitate their positive adjustments.

ObjectivesTo examine the 15-year secular trends of self-rated health (SRH) and correlates in Chinese adolescents in Hong Kong.DesignA territory-wide population-based panel data study.SettingAnonymised records of the annual health examination from the Student Health Service, Department of Health in Hong Kong.Participants397 324 students in Secondary 2 (US grade 8), 335 902 in Secondary 4 and 113 892 in Secondary 6 during the academic year 1999/2000 and 2014/15.Outcome measuresSRH and lifestyles were self-reported using standardised questionnaires. Sex-standardised and age-standardised prevalence of very poor/poor SRH and its secular annual changes across sex, grade, weight status, breakfast habits, and frequency/duration of aerobic exercises were examined. Their disparities over time were examined by interactions with the academic year in generalised estimating equations.ResultsThe overall prevalence of very poor/poor SRH increased from 9.3% (95% CI: 8.9% to 9.7%) in 1999/2000 to 15.5% (15.1% to 15.8%) in 2014/15. Very poor/poor SRH was more prevalent in girls (adjusted OR: 1.02), in those having unemployed parents (1.29), being overweight (1.42) or obese (2.62), eating breakfast away from home (1.27) and skipping breakfast (1.49) or doing ConclusionsIncreasing prevalence of very poor/poor SRH from 1999/2000 to 2014/15 was found among Hong Kong Chinese adolescents, which was greater in girls, adolescents being overweight/obese and those having unemployed parents or unhealthy lifestyles. Strategies to reduce health inequality should consider multiple factors, especially modifiable factors including lifestyles.

Background How weight status changes with time may affect self-esteem was seldom studied. We identified the distinct trajectories of overweight/obesity over age and assessed their associations with different domains of self-esteem in Hong Kong Chinese children. Methods Territory-wide longitudinal data of 48,558 children (girls: 50.0%; 6.3 ± 0.51 years) studying Primary 1 in the academic cohorts of 1995/96 and 1996/97 followed till Primary 6 were obtained from the Student Health Service of Hong Kong. Weight was annually measured and categorized as underweight/normal and overweight/obese and self-esteem was measured in Primary 6. Distinct trajectories of weight status were first identified using growth mixture modeling and their associations with low self-esteem were assessed by logistic regression. Results Four distinct overweight/obesity trajectories were identified: never (76.8%), late-onset (8.1%), early-onset (4.2%) and chronic (10.9%) overweight/obesity. Compared with children who were never overweight/obese, more of those in the late-onset or chronic overweight/obesity group showed low self-esteem and specific domains including general, social and academic/school-related (adjusted odds ratios: 1.20 - 1.43, all P < 0.001) except parent/home-related self-esteem (P = 0.36), whereas children being in the early-onset overweight/obesity group showed no significant difference (P ≥ 0.53) except a lower risk of low social self-esteem (adjusted odds ratio = 0.82, P = 0.03). Conclusions Late-onset or chronic overweight/obesity predicted low general, social and academic/school-related self-esteem. Children who successfully reduced weight may have equal levels of self-esteem or even better social self-esteem than those being always underweight/normal weight. Overweight/obese children had a vulnerability to self-esteem in non-domestic environments.

Background Face-to-face communication has reduced amidst the COVID-19 pandemic. We examined the associations between family communication and family wellbeing. Methods In an online survey of the Hong Kong Jockey Club SMART Family-Link Project in May 2021, 4981 Hong Kong Chinese adults (mean age 43.5 years, response rate 24.3%) reported family communication methods of face-to-face and instant messaging (IM) when the COVID-19 pandemic was severe (yes/no), communication contents that were neutral, positive, supportive, and negative (yes/no), and communication quality (0-10). The associations of family wellbeing (health, happiness, and harmony, 0-10) with communication methods and contents were examined using linear regression (β), adjusting for each other, sex, age, socioeconomic status, and number of cohabitants. The mediating effects of communication quality on these associations were examined. Prevalence estimates were weighted by sex, age and education of general population. Results 7.1% respondents reported no communication, 12.7% face-to-face only, 26.7% IM only, and 53.4% both. More communication contents were neutral (range 83.1-99.3%) than positive (42.1-62.2%), supportive (37.5-54.8%), and negative (10.9-34.5%). Communication quality was highest in using both methods (6.7 vs 4.5-6.6, all P≤0.02). Better family wellbeing was associated with using IM only (adjusted β: 0.37) and both methods (0.37) than face-to-face only and with positive (0.62) and supportive (0.45) contents (all P≤0.001). Communication quality mediated 35.2-93.5% of these associations. Conclusions Better family wellbeing was associated with IM and face-to-face communication and their contents, partly through communication quality. Key messages Family IM communication with positive and supportive contents may enhance family wellbeing amidst the COVID-19 pandemic.

Instant messaging (IM) is increasingly used for family communication amidst the COVID-19 pandemic. However, evidence remains scarce on how family e-chat groups were used and their associations with family and individual wellbeing amidst the pandemic. The numbers of family e-chat groups, functions used, and messages sent and received daily in groups were reported by 4890 adults in May 2020, and their associations with family wellbeing and personal happiness and the mediation effect of family communication quality were examined. Results showed that sending/receiving text messages was most commonly used, followed by receiving/sending photos/pictures, making voice calls, receiving/sending short videos and voice messages, and making video calls. Women and older people used more non-text functions. Higher levels of family wellbeing and personal happiness were associated with having more groups, receiving/sending photos/pictures, video calls, more IM functions used, and more IM messages received/sent daily. Forty-six point two to seventy-five point five percent of their associations with more groups and more functions used were mediated by family communication quality. People having more family e-chat groups and using more IM functions may be more resilient amidst the pandemic, while those without or with low use of family e-chat groups amidst the pandemic would need more attention and assistance in the presence of social distancing.

Background Sedentary behaviors are prevalent in Chinese children, however, the studies on their trends and socioeconomic disparities are scarce. We examined the time trends of daily television (TV) viewing and video game playing and the associated socioeconomic factors in Chinese children in Hong Kong, the most developed and westernized city in China. Methods In a panel data study involving 538,300 primary four and 510,294 primary six students from 1999/2000 to 2008/09, data on socioeconomic status, sedentary behaviors (TV viewing and video game playing) and other lifestyle habits were collected using a self-administered questionnaire. Trends in sedentary behaviors over time were assessed. Their socioeconomic disparities were examined by interactions in generalized estimating equations with the adjustment for weight status and extracurricular physical activities. Results The age and sex-standardized prevalence of ≥2 h daily TV viewing decreased from 51.4% (95% confidence interval [CI] 51.1–51.8%) in 1999/2000 to 43.8% (95% CI 43.4–44.2%) in 2008/09 (P for trend

Breakfast is deemed the most important meal of the day. We examined the prospective associations of breakfast habits with emotional/behavioral problems in adolescents and potential effect modification.115,217 Primary 6 students (United States Grade 6; mean age, 11.9; standard deviation [SD], 0.59 years) who attended the Student Health Service of Department of Health in Hong Kong in 2004/05, 2006/07, 2008/09 were followed till Secondary 6 (United States Grade 12). Emotional/behavioral problems were biennially examined using Youth Self-Report since Secondary 2 (United States Grade 8). Lifestyles were biennially examined using standardized questionnaires since Primary 6. Prospective associations of breakfast habit with emotional/behavioral problems and potential effect modification were examined using generalized estimating equations.Compared with eating breakfast at home, eating breakfast away from home was significantly associated with total emotional/behavioral problems and seven syndromes, including withdrawal, somatic complaints, anxiety/depression, thought problems, attention problems, delinquent behaviors, and aggressive behaviors (adjusted odds ratios [AORs] 1.22-2.04), while skipping breakfast showed stronger associations with the above problems and social problems (AORs 1.34-2.29). Stronger associations were observed in younger students for total and attention problems (P0.03) and in those with lower weight status for delinquent behaviors (P = 0.005).Eating breakfast away from home and especially skipping breakfast were prospectively associated with adolescent emotional/behavioral problems. The associations weakened with increasing age for total emotional/behavioral and attention problems, and weakened with higher weight status for delinquent behaviors, highlighting the vulnerability of younger and underweight children. If the associations are causal, increasing home breakfast may reduce adolescent emotional/behavioral problems and benefit psychosocial health.

BACKGROUND Family e-chat groups are commonly used, but little is known about its associations with family and individual well-being amidst the COVID-19 pandemic. OBJECTIVE Under the Hong Kong Jockey Club SMART Family-Link project, we examined the associations of family e-chat group use amidst the COVID-19 pandemic with family well-being and personal happiness, and the mediating effects of family communication quality on these associations. METHODS A territory-wide self-administered online survey was conducted in May 2020 on Chinese adults in Hong Kong. Respondents reported the number of family e-chat groups (0, 1, 2, ≥3), the instant messaging (IM) functions used (receiving/sending text messages, photos/pictures, short videos, voice messages, making voice calls and video calls), and the average numbers of IM messages sent and received daily (20) in family e-chat groups. Prevalence was weighted by sex, age, and education of the general population. Adjusted prevalence ratios (aPRs) for IM function use by demographics were calculated. Adjusted β for family well-being (health, harmony, and happiness), and personal happiness (all scale 0-10, higher scores indicate better outcomes) by number of family e-chat groups and IM function use were calculated, and the mediation effect of family communication quality on these associations examined. RESULTS Of 4890 respondents, 4046 (82.7%) had ≥1 family e-chat group. Sending/receiving text messages was most commonly used (weighted prevalence: 78.4%), followed by receiving/sending photos/pictures (76.5%), making voice calls (46.2%), receiving/sending short videos (37.2%) and voice messages (13.8%), and making video calls (8.2%). Women and older age were associated with having more groups (aPRs: 1.04-1.22, all P≤.03) and non-text function use (aPRs: 1.10-3.10, P≤.02). Better family well-being was associated with having more groups (β: 0.23-0.77), receiving/sending photos/pictures (β: 0.33), voice calls (β: 0.18), video calls (β: 0.45), more IM functions used (β: 0.43-0.51), and more IM messages received/sent daily (β: 0.38-0.54) (all P≤.01). Higher personal happiness was associated with having more groups (β: 0.30-0.72), receiving/sending photos/pictures (β: 0.30), video calls (β: 0.32), more IM functions use (β: 0.36-0.42) and more IM messages received/sent daily (β: 0.42-0.67) (all P≤.01). Family communication quality mediated the associations of more groups and more IM functions used with family well-being (mediated proportions: 75.5% and 69.5%, respectively) and personal happiness (mediated proportions: 66.4% and 46.2%, respectively). CONCLUSIONS This is the first study showing that, amidst the COVID-19 pandemic, having more family e-chat groups and using more IM functions including sending/receiving photos/pictures and making video calls in family e-chat groups, were associated with better family well-being and personal happiness, and about half to three-quarters of these associations were mediated by family communication quality. Prospective studies are needed to confirm the associations. People without or with low use of family e-chat groups would need more attention and assistance.

Family support through the sharing of information helps to shape and regulate the health and behaviours of family members, but little is known about how families are sharing COVID-19-related information, or about its associations with family communication quality and well-being. We examined the associations of COVID-19 information sharing methods with sociodemographic characteristics, the perceived benefits of information communication and technology (ICT) methods, and family communication quality and well-being in Hong Kong. Of 4852 respondents (53.2% female, 41.1% aged over 55 years), the most common sharing method was instant messaging (82.3%), followed by face-to-face communication (65.7%), phone (25.5%) and social media (15.8%). Female sex (adjusted prevalence ratio (aPR) 1.09), older age (aPRs 1.14–1.22) and higher household income (aPR 1.06) (all p ≤ 0.04) were associated with instant messaging use, while post-secondary education was associated with face-to-face (aPR 1.10), video call (aPR 1.79), and email (aPR 2.76) communications (all p ≤ 0.03). Each ICT sharing method used was associated with a higher likelihood of both reported benefits (aPRs 1.26 and 1.52), better family communication quality and family well-being (adjusted βs 0.43 and 0.30) (all p ≤ 0.001). We have first shown that COVID-19 information sharing in families using both traditional methods and ICTs, and using more types of methods, was associated with perceived benefits and better family communication quality and well-being amidst the pandemic. Sociodemographic differences in COVID-19 information sharing using ICTs were observed. Digital training may help enhance social connections and promote family well-being.

Solvothermal reactions of zinc and cadmium nitrates with 1,3,5-tri-4-pyridyl-1,2-ethenylbenzene (tpeb) in the presence of various carboxylic acids including 4-iodobenzoic acid (4-HIBA), benzene-1,4-dicarboxylic acid (1,4-H2BDC), 2,5-furandicarboxylic acid (2,5-H2FDC), 2,5-dibromoterephthalic acid (2,5-H2DBTPA), 1,2-cyclohexanedicarboxylic acid (1,2-H2CHDC), and 1,5-pentanedioic acid (1,5-H2PDC) gave rise to eight coordination complexes, viz, [Zn(tpeb)2(4-IBA)2]·2H2O (1), {[Cd(NO3)(tpeb)(4-IBA)]·H2O}n (2), {[Cd2(NO3)2(tpeb)2(1,4-BDC)]}n (3), {[Cd2(tpeb)2(2,5-FDC)2]·2H2O}n (4), [Cd(tpeb)(2,5-DBTPA)2]n (5), {[Cd2(H2O)2(tpeb)2(1,2-CHDC)2]·H2O}n (6), [Zn(tpeb)(1,2-CHDC)]n (7), and {[Zn(tpeb)(1,5-PDC)]·H2O}n (8). Compound 1 is a discrete mononuclear complex with its Zn(II) center coordinated by two pairs of tpeb and 4-IBA ligands. Compound 2 has a 2D waterfall-like network constructed from bridging [Cd(NO3)(4-IBA)] units with tpeb ligands. Compounds 3, 4, and 5 contain similar 1D [Cd(tpeb)]n chains, which are l...

Solvothermal reactions of Cd(NO3)2·4H2O with 4-pyr-poly-2-ene (ppene) in the presence of benzene-1,2-dicarboxylic acid (1,2-H2BDC), benzene-1,3-dicarboxylic acid (1,3-H2BDC), benzene-1,4-dicarboxylic acid (1,4-H2BDC), benzene-1,3,5-tricarboxylic acid (1,3,5-H3BTC), or 4,4′-oxidibenzoic acid (4,4′-H2OBA) afforded five Cd(II) coordination polymers [Cd(ppene)(1,2-BDC)]n (1), [Cd(ppene)(1,3-BDC)]n (2), [{Cd(ppene)(1,4-BDC)}·MeCN]n (3) (Liu et al. Inorg. Chem. Commun. 2015, 58, 1−4), [{Cd(ppene)(1,3,5-HBTC)}·0.5(ppene)]n (4), and [Cd(ppene)(4,4′-OBA)]n (5), respectively. Upon UV light irradiation, 1, 3, and 4 can undergo a double [2 + 2] cycloaddition reaction to yield their corresponding photoproducts including [Cd2(4-tp-3-lad)(1,2-BDC)2]n (1a, 4-tp-3-lad = 2,3,5,6-tetra(pyridin-4-yl)bicyclo[2.2.0]hexane), [{Cd2(4-tp-3-lad)(1,4-BDC)2}·2MeCN]n (3a), and [{Cd2(4-tp-3-lad)(1,3,5-HBTC)2}·(ppene)]n (4a) in a single-crystal-to-single-crystal manner. Compounds 1, 2, 4, 5, 1a, 3a, and 4a have been structurally charac...

In order to better solve the thermal management of high-power LED and facilitate its miniaturization, an active-passive combined heat dissipation method based on a dual synthetic jet actuator (DSJA) is proposed. Comparative analyses on heat dissipation characteristics and installation-space reductions of nine thermal management schemes are carried out. The results indicate that the temperature rapidly decreases and stabilizes once the actuator is activated. The heat dissipation effect based on DSJA is better than that based on synthetic jet actuator (SJA). The combination method with the vertical layout of DSJA makes the stable temperature of the LED and the installation space decrease 16 °C and 72.3% with respect to the commercial heat sink. Furthermore, a closed-loop system based on the combination method is developed to realize the autonomous control of the LED temperature within a setting temperature range. It is concluded that the operation duty cycle (ODC) reduces with the increase of the upper limit temperature, and there is an optimal impingement distance where the ODC is lowest of 29.1%. The closed-loop control will be greatly useful for the adaptive thermal management of electronic devices.

An innovative cooling technology based on a vectoring dual synthetic jet (DSJ) actuator is proposed, and then flow field and heat transfer characteristics are experimentally investigated. The deflection angle of vectoring DSJ can vary bilaterally and linearly with the movement of the adjustable slide. This novel feature makes the installation more flexible to obtain a maximum heat transfer coefficient and the effective heat transfer area is greatly extended, comparing to a conventional DSJ. The sweeping-flow capability can prevent the marginal region from working continuously at a high temperature. This cooling technology is expected to have important practical implications in space-constrained and large-area electronic cooling. Moreover, a model predicting the heat-transfer influence domain is established based on the vectoring angle of DSJ. The predicted results are validated to be in good agreement with the experimental results in the normal impingement region and the cross-flow region. It can provide a guide for properly arranging electric devices to improve the convective heat transfer.

A series of ((pyridinyl)-1H-pyrazolyl)pyridine (pypzpy) ligands in which the pyrazolyl ring at 1- and 3-positions is modified by two 2-, 3-, or 4-pyridyl groups were prepared. Reaction of CuI with 2-(1-(pyridin-2-yl)-1H-pyrazolyl)pyridine (2,2′-pypzpy) in MeCN at room temperature or solvothermal reaction of the same components at 120 °C afforded one binuclear complex [{(2,2′-pypzpy)Cu}(μ-I)]2 (1). Treatment of CuI with 3-(1-(pyridin-2-yl)-1H-pyrazolyl)pyridine (3,2′-pypzpy) at room temperature or at 120 °C produced one-dimensional (1D) polymer [{Cu3(μ3-I)3}(μ-3,2′-pypzpy)]n (2) and one two-dimensional (2D) polymer [{Cu2(μ-I)(μ3-I)}2(3,2′-pypzpy)2]n (3), respectively. Similar reactions of CuI with 4-(1-(pyridin-2-yl)-1H-pyrazolyl)pyridine (4,2′-pypzpy) at room temperature or at 150 °C yielded one 1D polymeric complex [{Cu(μ3-I)}2(4,2′-pypzpy)2{Cu(μ-I)}2]n (4). Complexes [{Cu3(μ3-I)3}(μ-2,3′-pypzpy)]n (5), [(CuI)(μ-2,3′-pypzpy)]2 (6), [(Cu2I2)(3,3′-pypzpy)] (7), [(CuI)(4,3′-pypzpy)] (8), [{Cu(μ3-I)}2(μ-2,4′...

An efficient approach to decarboxylative C3-acylation of benzothiophenes or benzofurans with α-oxocarboxylic acids via palladium-catalyzed C–H bond activation was developed. This method was compatible with a variety of functional groups and provided an attractive route to 3-acylbenzothiophenes and 3-acylbenzofurans in good to high yields.

The marine polychaete worm Perinereis aibuhitensis was used to study the genotoxic effects of mercuric chloride by means of the comet assay and micronucleus (MN) test. P. aibuhitensis was subjected in vivo to two different concentrations of mercuric chloride (0.05 mg L−1 and 0.5 mg L−1) for 96 h. The comet assay of coelomocytes demonstrated that TailDNA% values increased with extended exposure to or increased concentrations of HgCl2 (p

DMF-stabilized Au nanoparticles (NPs) with three different particle sizes were prepared by controlling the reaction temperatures and times. In the absence of any additional ligands, these Au NPs showed high catalytic activity in the Ullmann homocoupling of aryl iodides in DMF. The effects of Au particle size on the coupling reaction were investigated by the use of three Au catalysts with mean particle sizes of ca. 1.0 nm, 2.5 nm, and 5.5 nm, respectively. The catalytic activity of the Au NPs was found to be in the order of Au (2.5 nm)Au (1.0 nm)Au (5.5 nm), indicating that surface Au atoms do not have the same catalytic activity toward such a homocoupling reaction.

An efficient method for synthesis of 1,3-diynes through the CuI/1,10-phenanthroline-catalyzed oxidative decarboxylative homocoupling of aryl pioprolic acids in aqueous DMF has been developed. The catalytic system was suitable for a variety of arylpropiolic acids, and the corresponding 1,3-diynes could be prepared in high yields. The catalytic system was recovered from the organic products by filtration and its aqueous DMF filtrate retained good activity even after at least four cycles of use.

This work reported that Suzuki–Miyaura coupling reactions of arylboronic acid with aryl bromide or iodides were mediated by Pd(OAc)2 and 4-(benzylthio)-N,N,N-trimethylbenzenammonium chloride in the presence of Na2CO3 in water under the mild conditions. The corresponding Suzuki–Miyaura coupling products were obtained in good to excellent yields.

An experimental investigation is carried out to analyze the flow regime and impingement heat transfer of a dual synthetic jet (DSJ) actuator for the compact thermal management. The time-averaged flow field of DSJ is observed to consist of four regions, namely, the formation region, merging region, development region and decay region other than three regions of SJ without the merging region. The downstream vorticity-concentrated partitions of the SJ and the DSJ spread outwards at about 22.5° and 26.6°, respectively. The heat transfer characteristic of an impinging DSJ is analyzed by comparing with a synthetic jet (SJ). It is found that the local Nusselt number reaches a maximum at a same dimensionless impingement spacing of H/dh = 5.5 both for the SJ and the DSJ, and the maximum local Nusselt number of the impinging DSJ is 11.4% higher. The maximum area-averaged Nusselt number of the impinging DSJ is 8.6% higher at only half of H/dh than the impinging SJ, which is more preferable for the space-restricted electronic cooling. In addition, the effects of slot dimensions on the heat transfer of the impinging DSJ are studied. The peak Nusselt number is directly proportional to the slot neck length and inversely proportional to the slot aspect ratio at a same H/dh. The area-averaged Nusselt number reduces with the increase of the slot neck length at a smaller H/dh, and varies contrarily at a larger H/dh. The best heat transfer performance of the impinging DSJ is achieved at a midlevel aspect ratio. The results provide a design guideline for the cooling packages of space-restricted electronics.

Ten new complexes, [Cu2(L1)(NO3)2]·2H2O (1), [Cu4(L1)2]·4ClO4·H2O (2), [Cu2(L1)(H2O)2]·(adipate) (3), [Cu6(L1)2(m-bdc)4]·2DMF·5H2O (4), [Cu2(L1)(Hbtc)]·5H2O (5), [Cu2(L1)(H2O)2]·(ntc)·3H2O (6), [Co2(L2)]·[Co(MeOH)4(H2O)2] (7), [Co3(L2)(EtOH)(H2O)] (8), [Ni6(L2)2(H2O)4]·H2O (9) and [Zn4(L2)(OAc)2]·0.5H2O (10), have been synthesized. 1 displays a [Cu2(L1)(NO3)2] monomolecular structure. 2 shows a supramolecular chain including [Cu2L1]2+. In 3, two Cu(II) ions are connected by L1 to form a [Cu2(L1)(H2O)2]2+ cation. In 4, the m-bdc anions bridge Cu(II) ions and L1 anions to form a layer. Both 5 and 6 display 3-D supramolecular structures. 7 consists of both [Co2L2]2− and [Co(MeOH)4(H2O)2]2+ units. 8 and 9 show infinite chain structures. In 10, Zn(II) dimers are linked by L2 to generate a 3-D framework. The magnetic properties for 4 and 8 and the luminescent property for 10 have been studied.

An efficient approach to decarboxylative C3-acylation of benzothiophenes or benzofurans with α-oxocarboxylic acids via palladium-catalyzed C–H bond activation was developed. This method was compatible with a variety of functional groups and provided an attractive route to 3-acylbenzothiophenes and 3-acylbenzofurans in good to high yields.

An efficient method for synthesis of 1,3-diynes through the CuI/1,10-phenanthroline-catalyzed oxidative decarboxylative homocoupling of aryl pioprolic acids in aqueous DMF has been developed. The catalytic system was suitable for a variety of arylpropiolic acids, and the corresponding 1,3-diynes could be prepared in high yields. The catalytic system was recovered from the organic products by filtration and its aqueous DMF filtrate retained good activity even after at least four cycles of use.

This work reported that Suzuki–Miyaura coupling reactions of arylboronic acid with aryl bromide or iodides were mediated by Pd(OAc)2 and 4-(benzylthio)-N,N,N-trimethylbenzenammonium chloride in the presence of Na2CO3 in water under the mild conditions. The corresponding Suzuki–Miyaura coupling products were obtained in good to excellent yields.

The reaction of FeCl3 with a pincer ligand, 2,6-di(1H-pyrazol-3-yl)pyridine (bppyH2), produced a mononuclear Fe(III) complex [Fe(bppyH2)Cl3] (1), which could be reduced to the corresponding Fe(II) dichloride complex [Fe(bppyH2)Cl2] (2) by suitable reducing agents such as Cp2Co or Fe powder. 1 and 2 exhibited a reversible transformation from each other with appropriate redox reagents. 1 could be utilized as a pre-catalyst to initiate the ring-opening polymerization of e-caprolactone in the presence of alcohol but 2 did not work. The 1/alcohol system displayed characteristics of a well-controlled polymerization with the resulting poly(e-caprolactone) having low molecular weight distributions, a linear tendency of molecular weight evolution with conversion, and polymer growth observed for the sequential additions of e-caprolactone monomer to the polymerization reaction. The polymerization was completely turned off by the in situ reduction of the catalytic Fe center via Cp2Co and then turned back upon the addition of [Cp2Fe]PF6. The rate of polymerization was modified by switching in situ between the Fe(III) and Fe(II) species.

An unprecedented octahedral {Cd(30)} nanocage supported by twelve pendant-armed tetraacetate macrocyclic ligands was synthesized through the reaction of macrocyclic tetraethyl ester and Cd(OAc)(2)·2H(2)O in a 1 : 2 stoichiometry, where the surface photovoltage and photoluminescent properties have been studied for the nanocage.

Treatment of [CuCl(2)(bppyH(2))] (1, bppyH(2) = 2,6-di(1H-pyrazol-3-yl)pyridine) with 2 equiv. of AgNO(3) in DMF gave rise to a binuclear Cu(II) complex [Cu(2)(bppyH)(2)(NO(3))(2)] (bppyH = 2-(pyrazol-3-yl)-6-(pyrazolate)pyridine) (2). Complex 2 was characterized by elemental analysis, IR and single crystal X-ray diffraction. Complex 2 has a dimeric structure in which the two Cu(ii) centers are bridged by a couple of the in situ-generated bppyH(-) anions. Each Cu(II) center is further coordinated by one O atom of a NO(3)(-) anion and three N atoms of one bppyH(-) anion. Complex 2 exhibited a higher catalytic activity in the polymerization of methyl methacrylate (MMA) than the precursor complex 1. Even though the ratio of catalyst to MMA was raised up to 1 : 1500, the PDI for 2 (reaction time was fixed at 4 h) is 1.63 and the conversion is up to 72%. The effects of solvent, reaction temperature and the ratio of MMA to catalyst were also investigated.

Reactions of [Et4N][Tp*MoS(S)4] (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) (1) with 3 equiv. of CuX (X = Cl, Br, I, CN) or [Cu(MeCN)4]ClO4 in CH2Cl2-MeCN or CH2Cl2-DMF afforded [Et4N]2[Tp*Mo(μ3-S)3(CuCl)3(μ3-Cl)] (2), [Et4N][Tp*Mo(μ3-S)3(CuX)3] (3: X = Br; 4: X = I), [Et4N][Tp*MoO(μ-S)2(CuX)] (5: X = I; 6: X = CN) and [Tp*Mo(μ3-S)3Cu3(μ3-S')]4 (7). Compounds 2-7 were characterized by elemental analysis, IR spectra, UV-vis spectra, (1)H NMR, electrospray ion mass spectra (ESI-MS) and X-ray crystallography. The cluster dianion of 2 has a complete cubane-like [Tp*Mo(μ3-S)3(CuCl)3(μ3-Cl)] structure while the anion of 3 or 4 consists of an incomplete cubane-like [Tp*Mo(μ3-S)3(CuX)3] structure. The anion of 5 or 6 has a binuclear structure, in which one [Tp*MoO(μ-S)2] moiety and one CuX unit are linked by a pair of μ-S atoms. The structure of 7 may be considered as a supercube whose eight corners are occupied by four incomplete cubane-like [Tp*Mo(μ3-S)3Cu3] fragments and four μ3-S' atoms. The third-order nonlinear optical (NLO) properties of 2-6 in DMF were investigated by femtosecond degenerate four-wave mixing (DFWM) technique with a 80 fs pulse width at 800 nm. Compounds 2-6 exhibited good NLO performances and their NLO responses were enhanced relative to that of 1.

The reaction of [Ag(MeCN)(4)]ClO(4) with N,N,N',N'-tetra(diphenylphosphanylmethyl)ethylenediamine (dppeda) in CH(2)Cl(2)/MeOH afforded an unexpected cationic binuclear complex [Ag(2)(L(1))(2)(η,η-μ-ClO(4))(2)](ClO(4))(2) (L(1) = N,N'-bis(diphenylphosphanylmethyl)-3H-4,5-dihydroimidazole-1-ium) (1). Compound 1 was also prepared in high yield from reactions of [Ag(MeCN)(4)]ClO(4) with N,N'-bis(diphenylphosphanylmethyl)ethylenediamine (bdppeda) in the presence of formaldehyde (HCHO) or formic acid (HCOOH). Analogous reactions of AgCl with bdppeda and HCHO resulted in the formation a neutral binuclear complex [Ag(2)(L(2))(2)(μ-Cl)(2)] (L(2) = N,N-bis(diphenylphosphanylmethyl)-tetrahydroimidazole) (2). Treatment of 1 with concentrated HCl gave rise to a partially anion-exchanged product [Ag(2)(L(1))(2)(μ-Cl)(2)](ClO(4))(2) (3). Compounds 1 and 3 have a similar cationic binuclear structure, in which a [Ag(2)(η,η-μ-ClO(4))(2)] or [Ag(2)(μ-Cl)(2)] ring is sandwiched by two in situ-formed cationic L(1) ligands. The L(1) ligand may be generated by the Ag(I)-assisted condensation reaction between bdppeda and HCHO or HCOOH. Compound 2 holds a neutral binuclear structure, in which a [Ag(2)(μ-Cl)(2)] ring is connected by two in situ-formed L(2) ligands from its top and bottom sites. The neutral ligand L(2) may be produced from another Ag(I)-assisted condensation reaction between bdppeda and HCHO. The in situ formation of the L(1) and L(2) ligands provides a new route to the N-heterocyclic diphosphine ligands, and an interesting insight into the coordination chemistry of their metal complexes.

Reactions of Zn(NO3)2 with tetrakis(4-pyridyl)cyclobutane (tpcb) and 1,4-benzenedicarboxylic acid (1,4-H2BDC), 4,4′-biphenyldicarboxylic acid (4,4′-H2BPDB), 5-methyl-1,3-benzenedicarboxylic acid (5-CH3-1,3-H2BDC), 1,3,5-benzenetricarboxylic acid (1,3,5-H3BTC), 5-amino-1,3-benzenedicarboxylic acid (5-NH2-1,3-H2BDC), 4,4′-benzophenonedicarboxylic acid (4,4′-H2BPNDB) under solvothermal conditions led to the formation of six polydimensional coordination polymers {[Zn5(1,4-BDC)5(tpcb)2.5]·5H2O}n (1), {[Zn2(4,4′-BPDB)2(tpcb)]·0.5MeCN}n (2), [Zn2(OH2)2(5-CH3-1,3-BDC)2(tpcb)]n (3), {[Zn2(1,3,5-HBTC)2(tpcb)]·H2O}n (4), {[Zn2(5-NH2-1,3-BDC)2(tpcb)·H2O]}n (5), and [Zn2(4,4′-BPNDB)2(tpcb)]n (6). Compounds 1–6 were characterized by elemental analysis, IR, powder X-ray diffraction, and single crystal X-ray diffraction. Compounds 1 and 6 have different 3D (4,4) connected structures. Compounds 2–4 have different two-fold interpenetrating 3D (4,4)-connected structures. Compound 5 holds a 2D (3,4)-connected structure. The solid state luminescent properties of compounds 1–6 at ambient temperature were also investigated. The results provided some interesting insights into ligand effects on the structures and luminescent properties of zinc(II) coordination polymers.