氯化铵对绿色杜氏藻增殖的影响

报道了氯化铵对绿色杜氏藻增殖的影响情况。绿色杜氏藻的一次性培养试验结果 显示,氯化铵的浓度对绿色杜氏藻的增殖具有显著的影响。最适宜绿色杜氏藻增殖的浓度是 0．20～1．00 mmol／L,浓度值过高和过低均不利于绿色杜氏藻增殖,浓度过高时增殖缓慢,并且 稳定期短,易崩溃。在最适宜浓度水平时,绿色杜氏藻进入指数生长期较快,增殖速率值较大; 在1．00 mmol／L浓度时,绿色杜氏藻在稳定期获得最大的微藻密度值。     

红壤交换性碱和交换性酸的研究 Ⅱ.与中性盐NaCl和Ba(NO3)2的关系

提出一个测定Cl- —交换性碱的方法。用自动控制pH的滴定装置定量地研究了一个砖红壤胶体和一个红壤胶体在NaCl和Ba(NO3) 2 溶液中的交换性酸的变化。结果发现 ,砖红壤和红壤胶体在两种盐溶液中 ,在测定pH范围内只出现交换性酸 ,红壤胶体的交换性酸量比砖红壤胶体的大。随着盐浓度的增高 ,交换性酸量的增幅由大变小 ,明确地出现一折点 ,NaCl在 30 0mmolkg- 1左右 ,Ba(NO3) 2 在 1 2 0mmolkg- 1左右。pH对交换性酸有显著影响 ,在Ba(NO3) 2 溶液中随pH升高而增大 ,在NaCl溶液中则出现一峰值。     

Influence of high rates of topdressed KCl and K2SO4 on recovery of K,Cl, and SO4‐S by alfalfa and residual amount remaining in the soil

Abstract

This study was conducted to ascertain the percent of available K, Cl, and SO₄‐S recovered by alfalfa (Medicago sativa L. cv. ‘Vernal') herbage when various rates of K as KCl and K₂SO₄ were topdressed and also to determine where residual K, Cl, and SO₄‐S accumulated in the soil profile. An established stand of alfalfa growing on low fertility silt loam soil was topdressed in the spring of each of two harvest years with 0, 448, 896, 1344, and 1792 kg/ha of K as KCl or K₂SO₄. Four harvests were taken during each harvest year (1972 and 1973). Soil samples were taken during the autumn of 1973 to a depth of 91.4 cm in KCl‐fertilized plots, and to a depth of 76.2 cm in K₂SO₄‐fertilized and control plots.

Potassium recovery by alfalfa during two harvest years where K as KCl was applied at 448, 896, 1344, and 1792 kg/ha/yr was 56, 33, 20, and 17%, respectively. Recovery of available Cl from those same treatments was 30, 17, 12, and 10%, respectively. Where K as K₂SO₄ was applied at 448, 896, 1344, and 1792 kg/ha/yr, 55, 35, 27, and 22%, respectively, of available K was recovered. Recovery of available SO₄‐S from those same treatments was 16, 9, 7, and 5%, respectively. At the end of two years, a majority of the residual K was in the top 15.2 cm of soil. Residual Cl and SO₄‐S were concentrated at a depth of 30.5 to 76.2 cm in the soil profile.     

离子液体［Ｃ８Ｍｉｍ］Ｃｌ对泥鳅毒性效应的研究

以泥鳅(Misgurnus anguillicaudatus)为受试动物,采用急性毒性、遗传毒性及生理毒性试验,研究了[C8Mim]Cl对生物体的毒性效应.结果表明,[C8Mim] Cl对泥鳅有一定的毒性,其对泥鳅24h、48 h的LC50分别为324.13 mg/L、262.77mg/L,安全浓度为51.80 mg/L;各处理组的微核率均高于对照组(P＜0.05),且随着处理浓度的升高和时间的推移,红细胞微核率都有明显的升高;处理组血清中的谷丙转氨酶(GPT)和谷草转氨酶(GOT)活力均明显高于对照组(P＜0.05),且随离子液浓度升高以及时间的推移而增高;[C8Mim] Cl对泥鳅有显著的毒性作用.     

ClO2和Cl2对城市污水再生水消毒效果的比较

采用CIO2和Cl2分别对西安市城市污水再生水进行消毒中试试验.结果表明:当CIO2投加量大于7.67mg/L,经30 min接触消毒后,出水中未检出总大肠茵群,以氯代有机物为代表的消毒副产物(DBPs)较进水未有明显增加,COD和浊度的平均降幅为13.2%和17.9%,色度减少5度;当Cl2投加量大于6 mg/L,经30 min接触消毒后,出水中未检出总大肠菌群,二氯甲烷和三氯甲烷是进水时的2～3倍,三卤甲烷含量则达到进水时的4～6倍,同时生成少量的二氯一溴甲烷,COD和浊度平均降幅为17.8%和8.75%,色度减少5～10度.     

康氏木霉诱变前后纤维素酶组分的分离提纯

康氏木霉NN-15B_7株是康氏木霉854-B_2株经多次理化因素诱变,最后搭载卫星在太空条件作用下筛选出来的变异株.为比较诱变前后两个菌株所产纤维素酶的异同,本实验采用系列分离的方法,首先对其酶组分进行了分离提纯.粗酶粉经Scphadex G75凝胶过滤、DEAE-Scphadex A50离子交换层析和SP-Scphadex C50离子交换层析,分离得到了纯的C_1酶和Cx酶.经鉴定,C_1酶中含有微量Cx酶活力,PAG圆盘电泳只显示1条区带;Cx酶中均测不出C_1酶和β—葡萄糖苷酶活力,PAG圆盘电泳显示4条区带.诱变前后两株纤维素酶的组分分布未见差异.     

对饲料食盐含量的评说及其改进途径

以测Cl确定饲料中所含NaCl的结果严重失实，Na和Cl在饲料中的比例因料而异，从无定数，因此“食盐”和“食盐含量”等不实之词，应以Na、Cl含量表示，并以Na、Cl为单位计入饲粮中，以求符合动物的生理要求，进而可以取得预防和避免所谓的“食盐”中毒和节省饮水，降低舍内湿度之效，以NaHCO3补充饲粮中Na的不足，对蛋壳的结构有明显改善。     

氮钾肥对磷在红壤肥际微域中迁移转化的影响

在农田施肥中,氮肥和钾肥经常与磷肥一起施入土壤,一定程度上会影响磷的土壤化学行为。采用室内土柱实验研究了NH4Cl、KCl在与磷酸二氢钙(MCP)共施条件下对磷在红壤肥际微域中迁移和形态转化的影响。试验结果表明,共施NH4Cl或KCl未改变磷在红壤中的迁移距离,但对肥际微域中磷的形态转化产生了显著影响。与单施MCP相比,共施NH4Cl和KCl均显著降低了红壤肥际微域的土壤pH。在培养7 d和28 d时,共施NH4Cl均未对施肥点附近红壤的水溶性磷含量产生显著影响,而共施KCl在培养7 d时显著降低了水溶性磷含量,在培养28 d时却增加了水溶性磷含量。共施NH4Cl或KCl显著增加了红壤肥际微域内的酸溶性磷和有效磷含量。磷的迁移量回收结果表明,共施NH4Cl或KCl促进了磷从MCP中向红壤迁移,增加了磷的迁移量。     

Chlorine concentrations in alfalfa herbage and soil with KCl topdressing of a low fertility silt loam soil

Abstract

The purpose of this study was to determine the amount of Cl in plants and soil following topdressing of alfalfa with increasing amounts of KCl (0–0–60). The study was conducted with Ranger alfalfa on a low K Piano silt loam soil that had been topdressed twice during three years with a total of zero, 203, 406, 1220, and 2034 kg/ha of Cl as KCl (0, 224, 448, 1334, and 2240 kg/ha of K). Herbage was harvested annually three times at first flower plus an early October cut (4 cuts). The 3‐year average herbage yields were highest with 1220 kg/ha of topdressed Cl. Herbage yields decreased with 2034 kg/ha of Cl, but not significantly below that at 1220 kg/ha. Weakened and yellowed plants were noted in the spring of the second harvest year after 2034 kg/ha of Cl had been applied, and the first‐flower herbage contained 1.90% Cl. It was concluded that the weakened condition of the alfalfa was due to excess Cl.

Movement of Cl through the silt loam soil was rapid. The largest concentrations of Cl in the soil two years after the last KCl application were at the 76 to 91‐cm soil depth, the deepest soil sample tested.