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Isochronous mass spectrometry has been applied to neutron-deficient 58Ni projectile fragments at the HIRFL-CSR facility in Lanzhou, China. Masses of a series of short-lived T(z)=-3/2 nuclides including 41Ti, 45Cr, 49Fe, and 53Ni have been measured with a precision of 20-40 keV. The new data enable us to test for the first time the isobaric multiplet mass equation (IMME) in fp-shell nuclei. We observe that the IMME is inconsistent with the generally accepted quadratic form for the A=53, T=3/2 quartet. We perform full space shell model calculations and compare them with the new experimental results.

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High mountains may serve as a condenser for persistent organic pollutants. In the present study, soil and grass samples from Mt. Qomolangma region, China were collected from 4600 to 5620 m a.s.l and were analyzed for polycyclic aromatic hydrocarbons (PAHs) to determine if they are concentrated at colder, more elevated sites and to evaluate their possible resources and fractionation. The total PAHs concentration in soil samples was < 600 ng g −1 , the critical value to differentiate PAHs levels in remote and urban regions. This implied the PAHs levels at Mt. Qomolangma are relatively low and what one might expect in such a remote region of the world. These low values may represent a soil background for mid-latitude Northern Hemisphere soils away from the direct influence of an anthropogenic source. As for the distribution pattern, the low molecular weight PAHs were prone to accumulate at higher altitude, while the high molecular weight PAHs inversely related or unrelated with elevation. Based on high concentration of phenanthrene at elevated sample site and the ratios of individual PAHs, we deduced that home-heating combustion and vehicle emission may result in the constitution trait of PAHs in this mountain region. Monsoon traveling over India, Pakistan and other countries with dense population may carry contaminant to Mt. Qomolangma region.

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Previous literature has reported the fate of persistent organic pollutants (POPs) in mountainous regions, but the Himalayas have received little attention, and few results from this region have been published. The present study collected soil and grass samples from the Mt. Qomolangma (Everest) area, central Himalayas, China, from the elevation range 4700 to 5620 m. We analyzed all samples for organochlorine pesticides (OCPs) to determine the level of OCP contamination in the Qomolangma region. The soil samples contained 0.385 to 6.06 ng g(-1) of DDT only, and these concentrations were lower than those from Europe and mountains close to industrial emissions. Our study detected a number of OCPs in the grass samples, such as hexachlorocyclohexane (HCH) (0.354 to 7.82 ng g(-1)), hexachlorobenzene (HCB) (0.0156 to 1.25 ng g(-1)), endosulfan (0.105 to 3.14 ng g(-1)), and DDT components (1.08 to 6.99 ng g(-1)). Their concentrations were higher than those in pine needles from Alberta, Canada. Our measurements of HCH and DDT in grass samples showed the same or slightly higher concentration levels than reported in moss from Mt. Qomolangma 15 years ago. This result and the analysis of isomer ratios (alpha/gamma-HCH and p-p'-DDE/p-p'-DDT) indicate recent releases of OCPs from a nearby region, possibly from dicofol use in India. We also investigated the elevation distribution of OCPs and found that HCH and HCB were progressively concentrated in colder, higher elevation sites. A bioconcentration factor (BCF) of grass was calculated, and the BCF values increased with the increasing elevation, indicating that the cold condensation of POPs at high-elevation sites may increase the potential threat to vegetation and the food chain in the mountain ecosystem.