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Two cladding methods for NdFeB powders, i.e., the modified organic silicon (MOS) cladding and the dichromate passivation reducing (DPR) cladding are exploited respectively for the preparation of polymer-bonded magnet and metal-bonded magnet. The effects of their cladding conditions and coating compositions, together with the effects of modifying additives are discussed. Compared with the conventional polymer-bonded magnet, MOS polymer-bonded sample shows better comprehensive properties including magnetic properties, compression strength and corrosion resistance. Providing a feasible method for Nd-Fe-B type metal-bonded magnet, DPR Sn-bonded NdFeB magnet presents superior compression strength despite a little inferior magnetic property.

Predators and parasites have synergistic effects on the phenotype of the species they share as prey and host. Experimental studies that incorporate the interactions between predation and parasitism are, however, scarce in small-mammal populations. Our previous work has shown that the combined effects of predation and coccidian infection reduce overwinter survival and population density in root voles (Microtus oeconomus). Here, we examined the separate and combined effects of these two drivers on the population growth of root voles during the breeding season. We carried out a two-level factorial experiment, in which we manipulated predator exclusion and the removal of parasites in enclosures and measured survival, fecal corticosterone metabolite (FCM) concentration, recruitment, and population density. An expected synergistic effect of predators and parasites on vole population was not found, due to no effect of parasites on FCM level and recruitment rate during the period of the experiment. Instead, we found phase-related effects of predation on demography. Predation reduced the survival rate of voles in spring, which was intensified by parasite infection. Predation risk reduced recruitment rate in early summer by elevating FCM levels. Consequently, both direct and indirect effects of predation lowered population density during the experimental period. In addition, for populations free of predators, the peak density that occurred in early autumn elevated FCM level of adult voles, which reduced recruitment rates and halted population growth. Moreover, predation, parasites, and density affected the quality of the offspring. Our study suggests that multiple regulation processes influence population fluctuations during the breeding season. We conclude that a population experiencing stress acts as a common interface through which interactions between intrinsic and extrinsic factors can be important determinants of fluctuations. We propose a new hypothesis of integrative stress effects to explain small-mammal population fluctuations.