The Compact Pulsed Hadron Source: A Design Perspective

During the past. decades, large-scale national neutron sources have been developed in Asia, Europe, and North America. Complementing such efforts, compact hadron beam complexes and neutron sources intended to serve primarily universities and industrial institutes have been proposed, and some have recently been established. Responding to the demand in China for pulsed neutron/proton-beam platforms that are dedicated to fundamental and applied research for users in multiple disciplines from materials characterization to hadron therapy and radiography to accelerator-driven sub-critical reactor systems (ADS) for nuclear waste transmutation, we have initiated the construction of a compact, yet expandable, accelerator complex-the Compact Pulsed Hadron Source (CPHS). It consists of an accelerator front-end (a high-intensity ion source, a 3-MeV radio-frequency quadrupole linac (RFQ), and a 13-MeV drift-tube linac (DTL)), a neutron target station (a beryllium target with solid methane and room-temperature water moderators/reflector), and experimental stations for neutron imaging/radiography, small-angle scattering, and proton irradiation. In the future, the CPHS may also serve as an injector to a ring for proton therapy and radiography or as the front end to an ADS test facility. In this paper, we describe the design of the CPHS technical systems and its intended operation.

长白山森林生态系统中的稀有和濒危多孔菌

In last 10 years,extensive field inventories were carried out to investigate Polypore species, the major wood decaying fungi in the Changbaishan Nature Reserve of Northeastern China. The following 27 species were treated as rare or threathened species: Amylocystis lapponica (Romell) Singer, Anomoporia albolutescens (Romell) Pouzar, Anomoporia bombycina (Fr.) Pouzar, Anomoporia vesiculosa Y.C. Dai & Niemel, Antrodia carbonica (Overh.) Ryvarden & Gilb., Antrodia crassa (P. Karst.) Ryvarden, Antrodiella citrinella Niemel & Ryvarden, Diplomitoporus flavescens (Bres.) Dománski, Donkioporia expansa (Desm.) Kotl. & Pouzar, Gloeophyllum carbonarium (Berk. & M.A. Curtis) Ryvarden, Haploporus odorus (Sommerf.) Bondartsev & Singer, Inonotopsis subiculosa (Peck) Parmasto, Nigroporus ussuriensis (Bondartsev & Ljub.) Y.C. Dai & Niemela, Oxyporus sinensis X.L. Zeng, Parmastomyces taxi (Bondartsev) Y.C. Dai & Niemela, Phellinidium sulphurascens (Pilat) Y.C. Dai, Phellinus vaninii Ljub., Polyporus vassilievae Thorn, Pycnoporellus fulgens (Fr.) Donk, Skeletocutis brevispora Niemela, Skeletocutis ochroalba Niemela, Skeletocutis perennis Ryvarden, Trechispora candidissima (Schwein.) Bondartsev & Singer, Wolfiporia dilatohypha Ryvarden & Gilb., Wolfiporia curvispora Y.C. Dai, Wrightoporia avellanea (Bres.) Pouzar and Wrightoporia lenta (Oveh. & J. Lowe) Pouzar. Polypores are richer in East Asia than in Europe and North America, not only because of destructive galciations and fewer hosts in the latters, but also because of the geography. NE Asia is a link between Europe and North America. Changbaishan Nature Reserve is very rich in polypores, and over 260 species were recorded in the reserve. Some rare species in North America and Europe, for instance, Anomoporia albolutescens, Antrodia crassa, Diplomitoporus flavescens, Inonotopsis subiculosa and Skeletocutis ochroalba etc. were found in Changbaishan Nature Reserve as well, and these species are in fact rare in the earth. Most of the 27 species occurred on fallen trunks or rotten wood in the reserve, but some of them grew on living trees. 18 species occured on substrate of gymnosperms, and 9 species grew on wood of angiosperm.Among the 27 species, 7 species caused a brown rot,and 20 species produced a white rot. The morphology, substrate and ecology of each species were briefly discussed. The most important tool for polypore conservation is the conservation of their habitats, and it is necessary to study the ecology of the rare and threathened species of polypores in the Changbaishan Nature Reserve. Because most of polypores live on the substrate of fallen trunks and rotten wood, it is very important to keep such substrate in the ecosystem.